<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2021 Workiva-->
<!--r:ce34697f-7bab-4fa7-9389-712dbab596a1,g:b00a47ae-ef0b-467d-9f01-c19ea7865e9b-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/UNAUDITEDCONSOLIDATEDSTATEMENTSOFOPERATIONS" xlink:type="simple" xlink:href="clh-20210630.xsd#UNAUDITEDCONSOLIDATEDSTATEMENTSOFOPERATIONS"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/UNAUDITEDCONSOLIDATEDSTATEMENTSOFOPERATIONS" xlink:type="extended" id="i2e26e2b5213a4dee83a42fd1fef2ae4b_UNAUDITEDCONSOLIDATEDSTATEMENTSOFOPERATIONS">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_dfe14479-2f70-44fc-b580-55fc662f5757" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_RevenuesAbstract_dfe14479-2f70-44fc-b580-55fc662f5757" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_f2b9d6cb-d901-4023-a71b-c42a7aadc8ac" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_dfe14479-2f70-44fc-b580-55fc662f5757" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_f2b9d6cb-d901-4023-a71b-c42a7aadc8ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenueAbstract_3be255a0-f794-4284-81cd-fd1b5869b6ad" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CostOfRevenueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_CostOfRevenueAbstract_3be255a0-f794-4284-81cd-fd1b5869b6ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_171e6c78-1ea3-48fe-beb5-b8c0d4dcc860" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_3be255a0-f794-4284-81cd-fd1b5869b6ad" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_171e6c78-1ea3-48fe-beb5-b8c0d4dcc860" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_5fd7c0a8-a82b-4034-aa61-e6b63b4a6619" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_5fd7c0a8-a82b-4034-aa61-e6b63b4a6619" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AccretionOfEnvironmentalLiabilities_bc4856fc-9bff-4f89-be4f-c803b2f6415c" xlink:href="clh-20210630.xsd#clh_AccretionOfEnvironmentalLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_clh_AccretionOfEnvironmentalLiabilities_bc4856fc-9bff-4f89-be4f-c803b2f6415c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_7572387b-d9e2-423b-84b4-29964f034753" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_7572387b-d9e2-423b-84b4-29964f034753" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_275ee3d1-3b83-4d5e-a01c-182c2a236cb0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_OperatingIncomeLoss_275ee3d1-3b83-4d5e-a01c-182c2a236cb0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_8305a24d-4e70-4679-bbf0-36ef886212d8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_8305a24d-4e70-4679-bbf0-36ef886212d8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_4b7a0380-e8f3-4e38-9cf9-800e9b440af4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_4b7a0380-e8f3-4e38-9cf9-800e9b440af4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_bb84a0f9-849e-4edb-a891-77199d781cc1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_bb84a0f9-849e-4edb-a891-77199d781cc1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_d445dac0-cf49-4295-af3a-891b2900ed73" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_d445dac0-cf49-4295-af3a-891b2900ed73" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_e4dedf12-6de7-499f-a4bb-09ddf4f0906d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_e4dedf12-6de7-499f-a4bb-09ddf4f0906d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_d3b08738-752a-4e12-baeb-516a2e9a614e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_NetIncomeLoss_d3b08738-752a-4e12-baeb-516a2e9a614e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareAbstract_b5832c38-932c-4baa-b662-796d3592523c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EarningsPerShareAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_EarningsPerShareAbstract_b5832c38-932c-4baa-b662-796d3592523c" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_4cd239db-b780-4bd3-84dc-202797c3d900" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_b5832c38-932c-4baa-b662-796d3592523c" xlink:to="loc_us-gaap_EarningsPerShareBasic_4cd239db-b780-4bd3-84dc-202797c3d900" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_d35d251f-b543-403f-8b75-79cb061b4601" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_b5832c38-932c-4baa-b662-796d3592523c" xlink:to="loc_us-gaap_EarningsPerShareDiluted_d35d251f-b543-403f-8b75-79cb061b4601" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2b78bd5b-faff-4656-80b4-1a3dec6f731d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2b78bd5b-faff-4656-80b4-1a3dec6f731d" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_6f8dc75c-b753-4426-b355-ae850261955e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_6f8dc75c-b753-4426-b355-ae850261955e" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_8c89bd2e-6080-42e7-a890-3fbc41e79c3d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_28cb4bae-3852-4b0d-8062-1890aa2f06a3" xlink:to="loc_us-gaap_StatementTable_8c89bd2e-6080-42e7-a890-3fbc41e79c3d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_f77a3aad-9d81-4c89-92f1-d2435fa92276" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_8c89bd2e-6080-42e7-a890-3fbc41e79c3d" xlink:to="loc_srt_ProductOrServiceAxis_f77a3aad-9d81-4c89-92f1-d2435fa92276" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_f77a3aad-9d81-4c89-92f1-d2435fa92276_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_f77a3aad-9d81-4c89-92f1-d2435fa92276" xlink:to="loc_srt_ProductsAndServicesDomain_f77a3aad-9d81-4c89-92f1-d2435fa92276_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_7040c9a1-54e0-4744-88a4-5c42167fa373" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_f77a3aad-9d81-4c89-92f1-d2435fa92276" xlink:to="loc_srt_ProductsAndServicesDomain_7040c9a1-54e0-4744-88a4-5c42167fa373" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServiceMember_fe576ea9-2ca9-4f6a-a463-c9d5747ae8f5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ServiceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_7040c9a1-54e0-4744-88a4-5c42167fa373" xlink:to="loc_us-gaap_ServiceMember_fe576ea9-2ca9-4f6a-a463-c9d5747ae8f5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductMember_c446bc3d-6a4a-4435-8099-fcdb0dd34b94" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProductMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_7040c9a1-54e0-4744-88a4-5c42167fa373" xlink:to="loc_us-gaap_ProductMember_c446bc3d-6a4a-4435-8099-fcdb0dd34b94" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/UNAUDITEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY" xlink:type="simple" xlink:href="clh-20210630.xsd#UNAUDITEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/UNAUDITEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY" xlink:type="extended" id="i8806801384a74a0584e3bef7493e0929_UNAUDITEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_9536d46c-1f9a-4dc3-b27b-bed1a574acd4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9536d46c-1f9a-4dc3-b27b-bed1a574acd4" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssued_d4647535-db0a-4111-95dd-632bd042cdc2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_SharesIssued_d4647535-db0a-4111-95dd-632bd042cdc2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_41c36825-2134-457c-8a7a-0327b424ec7d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockholdersEquity_41c36825-2134-457c-8a7a-0327b424ec7d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_979c8188-331f-4c58-8b82-03341f5dd86d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_NetIncomeLoss_979c8188-331f-4c58-8b82-03341f5dd86d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_284458fc-42cb-445e-83b2-01e382025ebd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_284458fc-42cb-445e-83b2-01e382025ebd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_88aff443-b6ca-44ce-aaf7-3c3b64c3e5af" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_88aff443-b6ca-44ce-aaf7-3c3b64c3e5af" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_d9d56cc9-c905-409f-90f5-440eff0d34d0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_d9d56cc9-c905-409f-90f5-440eff0d34d0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_b05e40fd-9d47-4e01-8650-a932b887a2e8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_b05e40fd-9d47-4e01-8650-a932b887a2e8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_484fb77b-359d-4b3d-b061-da55282b28b8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_484fb77b-359d-4b3d-b061-da55282b28b8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_ebf1dbf7-15c4-4f90-9fa1-9e83cbb70225" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1e341899-afaf-436e-8101-d7f39a124205" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_ebf1dbf7-15c4-4f90-9fa1-9e83cbb70225" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssued_1cdae053-c399-43fc-9595-083b062829fe" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SharesIssued"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_f4808c9c-8e65-4517-bddf-9b6193de3b1a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_baae282b-1c8d-4dbc-82f9-a1c80b2835aa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_9536d46c-1f9a-4dc3-b27b-bed1a574acd4" xlink:to="loc_us-gaap_StatementTable_baae282b-1c8d-4dbc-82f9-a1c80b2835aa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_cce03087-b2d2-4c47-a97f-a3edabe2b18c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_baae282b-1c8d-4dbc-82f9-a1c80b2835aa" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_cce03087-b2d2-4c47-a97f-a3edabe2b18c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_cce03087-b2d2-4c47-a97f-a3edabe2b18c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cce03087-b2d2-4c47-a97f-a3edabe2b18c" xlink:to="loc_us-gaap_EquityComponentDomain_cce03087-b2d2-4c47-a97f-a3edabe2b18c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cce03087-b2d2-4c47-a97f-a3edabe2b18c" xlink:to="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_25ded157-b4e3-4745-a28c-fa744c09dc20" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:to="loc_us-gaap_CommonStockMember_25ded157-b4e3-4745-a28c-fa744c09dc20" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_64d3b84c-ba4c-42d3-9efb-6e194b21091c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_64d3b84c-ba4c-42d3-9efb-6e194b21091c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1c7c83ed-fe40-4ebc-98dc-51a121fb928d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1c7c83ed-fe40-4ebc-98dc-51a121fb928d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_39066eea-4d58-4c0c-a3fb-25a710d40846" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0d33479b-22d4-43ca-93b0-3645e2318bd8" xlink:to="loc_us-gaap_RetainedEarningsMember_39066eea-4d58-4c0c-a3fb-25a710d40846" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/REVENUESDisaggregationofRevenueDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#REVENUESDisaggregationofRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/REVENUESDisaggregationofRevenueDetails" xlink:type="extended" id="ibfebc7a9eea143cca1948c5333154504_REVENUESDisaggregationofRevenueDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_5c49b321-1563-4fc8-a557-078000fdfb16" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_80917b41-4ce7-43de-858a-c818f7772198" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_5c49b321-1563-4fc8-a557-078000fdfb16" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_80917b41-4ce7-43de-858a-c818f7772198" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_5c49b321-1563-4fc8-a557-078000fdfb16" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_59a20b99-8368-4f07-acb3-a4471999525c" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:to="loc_srt_ConsolidationItemsAxis_59a20b99-8368-4f07-acb3-a4471999525c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_59a20b99-8368-4f07-acb3-a4471999525c_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_59a20b99-8368-4f07-acb3-a4471999525c" xlink:to="loc_srt_ConsolidationItemsDomain_59a20b99-8368-4f07-acb3-a4471999525c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_f6d90151-74a0-4faa-becb-e9d7bc7dd0a4" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_59a20b99-8368-4f07-acb3-a4471999525c" xlink:to="loc_srt_ConsolidationItemsDomain_f6d90151-74a0-4faa-becb-e9d7bc7dd0a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_3ee5853e-5055-4064-a253-dc7c6209d579" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_f6d90151-74a0-4faa-becb-e9d7bc7dd0a4" xlink:to="loc_us-gaap_OperatingSegmentsMember_3ee5853e-5055-4064-a253-dc7c6209d579" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_95fef1f7-7e4a-478d-b46b-c3966fb73c78" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_f6d90151-74a0-4faa-becb-e9d7bc7dd0a4" xlink:to="loc_us-gaap_CorporateNonSegmentMember_95fef1f7-7e4a-478d-b46b-c3966fb73c78" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a" xlink:to="loc_us-gaap_SegmentDomain_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4235f252-4c16-4986-ac77-93afe5379d4c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_0f0858d7-e50a-4e1c-9bcf-a7a8ae7e017a" xlink:to="loc_us-gaap_SegmentDomain_4235f252-4c16-4986-ac77-93afe5379d4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_e73ed750-b886-454d-aa20-04403332625b" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4235f252-4c16-4986-ac77-93afe5379d4c" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_e73ed750-b886-454d-aa20-04403332625b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_3f5149e3-d1c3-4f93-8e6b-6d2a4a13369c" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4235f252-4c16-4986-ac77-93afe5379d4c" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_3f5149e3-d1c3-4f93-8e6b-6d2a4a13369c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_1b2c6dde-f4ee-4234-bb2e-7775a86429ee" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:to="loc_srt_StatementGeographicalAxis_1b2c6dde-f4ee-4234-bb2e-7775a86429ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_1b2c6dde-f4ee-4234-bb2e-7775a86429ee_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_1b2c6dde-f4ee-4234-bb2e-7775a86429ee" xlink:to="loc_srt_SegmentGeographicalDomain_1b2c6dde-f4ee-4234-bb2e-7775a86429ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_92c68484-9102-4e63-b3bf-61ead3bf8887" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_1b2c6dde-f4ee-4234-bb2e-7775a86429ee" xlink:to="loc_srt_SegmentGeographicalDomain_92c68484-9102-4e63-b3bf-61ead3bf8887" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_eba78748-a0ec-4034-aaa7-d27e0ee52433" xlink:href="https://xbrl.sec.gov/country/2021/country-2021.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_92c68484-9102-4e63-b3bf-61ead3bf8887" xlink:to="loc_country_US_eba78748-a0ec-4034-aaa7-d27e0ee52433" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_2f790cf0-e6b8-4e86-95ca-32f25557d61f" xlink:href="https://xbrl.sec.gov/country/2021/country-2021.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_92c68484-9102-4e63-b3bf-61ead3bf8887" xlink:to="loc_country_CA_2f790cf0-e6b8-4e86-95ca-32f25557d61f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_2c10a6f3-393e-4bc7-b232-d009cde11802" xlink:to="loc_srt_ProductOrServiceAxis_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f" xlink:to="loc_srt_ProductsAndServicesDomain_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_bfec49e3-5431-4219-bd6a-8ec2dfb5c63f" xlink:to="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_TechnicalServicesMember_3bd85678-eb12-4ee8-9572-db0710098496" xlink:href="clh-20210630.xsd#clh_TechnicalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:to="loc_clh_TechnicalServicesMember_3bd85678-eb12-4ee8-9572-db0710098496" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_FieldandEmergencyResponseMember_8fcccbeb-11d2-4894-965a-f0bbe60e3541" xlink:href="clh-20210630.xsd#clh_FieldandEmergencyResponseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:to="loc_clh_FieldandEmergencyResponseMember_8fcccbeb-11d2-4894-965a-f0bbe60e3541" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_IndustrialServicesAndOtherMember_308c2ac4-6fbd-4574-adc1-ab62239bf03a" xlink:href="clh-20210630.xsd#clh_IndustrialServicesAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:to="loc_clh_IndustrialServicesAndOtherMember_308c2ac4-6fbd-4574-adc1-ab62239bf03a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetlyKleenEnvironmentalServicesMember_fd738df3-22b6-450c-8ef7-059fdd91117b" xlink:href="clh-20210630.xsd#clh_SafetlyKleenEnvironmentalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:to="loc_clh_SafetlyKleenEnvironmentalServicesMember_fd738df3-22b6-450c-8ef7-059fdd91117b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenOilMember_13afb99a-28cd-41e5-9334-b5d7396280f1" xlink:href="clh-20210630.xsd#clh_SafetyKleenOilMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_41857174-de2e-4437-98c8-9373f4ea083b" xlink:to="loc_clh_SafetyKleenOilMember_13afb99a-28cd-41e5-9334-b5d7396280f1" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/REVENUESAdditionalInformationDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#REVENUESAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/REVENUESAdditionalInformationDetails" xlink:type="extended" id="i42220054cbed410bbc070ad5aefb6300_REVENUESAdditionalInformationDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_5393a28b-f24d-446b-bd1f-57ff77c43c2f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfRevenueSources_bf1d53d4-3dff-48c5-a3fa-a8e00e2489bf" xlink:href="clh-20210630.xsd#clh_NumberOfRevenueSources"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_5393a28b-f24d-446b-bd1f-57ff77c43c2f" xlink:to="loc_clh_NumberOfRevenueSources_bf1d53d4-3dff-48c5-a3fa-a8e00e2489bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_DeferredContractCostRecognitionPeriod_35346680-9ddc-41ff-8458-c72811dcc716" xlink:href="clh-20210630.xsd#clh_DeferredContractCostRecognitionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_5393a28b-f24d-446b-bd1f-57ff77c43c2f" xlink:to="loc_clh_DeferredContractCostRecognitionPeriod_35346680-9ddc-41ff-8458-c72811dcc716" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_72e3d6d9-e1ad-49b5-9e19-11bb7a1b0855" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_5393a28b-f24d-446b-bd1f-57ff77c43c2f" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_72e3d6d9-e1ad-49b5-9e19-11bb7a1b0855" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_5632ec8e-ed20-4998-9d09-011f8ed554c4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_72e3d6d9-e1ad-49b5-9e19-11bb7a1b0855" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_5632ec8e-ed20-4998-9d09-011f8ed554c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5632ec8e-ed20-4998-9d09-011f8ed554c4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5632ec8e-ed20-4998-9d09-011f8ed554c4" xlink:to="loc_us-gaap_SegmentDomain_5632ec8e-ed20-4998-9d09-011f8ed554c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_1a184f08-d6c8-4aa7-b4ce-605e9774f8d0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5632ec8e-ed20-4998-9d09-011f8ed554c4" xlink:to="loc_us-gaap_SegmentDomain_1a184f08-d6c8-4aa7-b4ce-605e9774f8d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_70a5ae01-f315-4859-ae16-e511eaab21ce" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_1a184f08-d6c8-4aa7-b4ce-605e9774f8d0" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_70a5ae01-f315-4859-ae16-e511eaab21ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_d55f5e3a-5299-42f7-a08d-c9e8cc8d50db" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_1a184f08-d6c8-4aa7-b4ce-605e9774f8d0" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_d55f5e3a-5299-42f7-a08d-c9e8cc8d50db" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/BUSINESSCOMBINATIONSDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#BUSINESSCOMBINATIONSDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/BUSINESSCOMBINATIONSDetails" xlink:type="extended" id="ib2244aad553f4e2ab4b4cb1c9d7c0c89_BUSINESSCOMBINATIONSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_a2bbe98c-cc33-4849-915d-9a484bf7ad1b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_a2bbe98c-cc33-4849-915d-9a484bf7ad1b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_25429329-2913-485c-8cdb-e2933a758b8c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillAcquiredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_25429329-2913-485c-8cdb-e2933a758b8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionConsiderationTransferred_041bc5eb-7d7b-4910-983f-de5d8fc8302a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetAcquisitionConsiderationTransferred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_us-gaap_AssetAcquisitionConsiderationTransferred_041bc5eb-7d7b-4910-983f-de5d8fc8302a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityNumberOfEmployees_fbedd8a7-25ad-468f-bed0-c0ebd8ba4276" xlink:href="https://xbrl.sec.gov/dei/2021/dei-2021.xsd#dei_EntityNumberOfEmployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_dei_EntityNumberOfEmployees_fbedd8a7-25ad-468f-bed0-c0ebd8ba4276" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfServiceLocation_b3e69295-0f1a-4bc1-a10f-bc1d6829a931" xlink:href="clh-20210630.xsd#clh_NumberOfServiceLocation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_clh_NumberOfServiceLocation_b3e69295-0f1a-4bc1-a10f-bc1d6829a931" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_0fb65b32-e7e2-4acc-ae2e-953523b2b6a0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_0fb65b32-e7e2-4acc-ae2e-953523b2b6a0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_395355bb-2412-49d1-9a3c-8de2935e47ad" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_e743124f-8d0a-45c3-926a-f9badc6e29c2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_e743124f-8d0a-45c3-926a-f9badc6e29c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e743124f-8d0a-45c3-926a-f9badc6e29c2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_e743124f-8d0a-45c3-926a-f9badc6e29c2" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e743124f-8d0a-45c3-926a-f9badc6e29c2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_031c2f17-2d38-4399-8a89-766c6e2c2741" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_e743124f-8d0a-45c3-926a-f9badc6e29c2" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_031c2f17-2d38-4399-8a89-766c6e2c2741" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_A2021AcquisitionsMember_3c989ea0-91f9-4b77-8454-e5fffd6d4f48" xlink:href="clh-20210630.xsd#clh_A2021AcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_031c2f17-2d38-4399-8a89-766c6e2c2741" xlink:to="loc_clh_A2021AcquisitionsMember_3c989ea0-91f9-4b77-8454-e5fffd6d4f48" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_A2020AcquisitionsMember_75a32e05-be90-4408-8b8f-137eff434d82" xlink:href="clh-20210630.xsd#clh_A2020AcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_031c2f17-2d38-4399-8a89-766c6e2c2741" xlink:to="loc_clh_A2020AcquisitionsMember_75a32e05-be90-4408-8b8f-137eff434d82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_HydroChemPSCMember_5a7a7bbe-5e50-4167-8c18-4625531bd1e2" xlink:href="clh-20210630.xsd#clh_HydroChemPSCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_031c2f17-2d38-4399-8a89-766c6e2c2741" xlink:to="loc_clh_HydroChemPSCMember_5a7a7bbe-5e50-4167-8c18-4625531bd1e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionAxis_eb428115-4103-4354-bf7f-43974c1300a5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:to="loc_us-gaap_AssetAcquisitionAxis_eb428115-4103-4354-bf7f-43974c1300a5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_eb428115-4103-4354-bf7f-43974c1300a5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetAcquisitionAxis_eb428115-4103-4354-bf7f-43974c1300a5" xlink:to="loc_us-gaap_AssetAcquisitionDomain_eb428115-4103-4354-bf7f-43974c1300a5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_d8aca691-53db-4be8-8e39-6dcf5e4f9a5e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetAcquisitionAxis_eb428115-4103-4354-bf7f-43974c1300a5" xlink:to="loc_us-gaap_AssetAcquisitionDomain_d8aca691-53db-4be8-8e39-6dcf5e4f9a5e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_VertexEnergyIncMember_06b50f07-2d38-4f6f-912e-dda2271c6157" xlink:href="clh-20210630.xsd#clh_VertexEnergyIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionDomain_d8aca691-53db-4be8-8e39-6dcf5e4f9a5e" xlink:to="loc_clh_VertexEnergyIncMember_06b50f07-2d38-4f6f-912e-dda2271c6157" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_a9795ccd-01f8-464a-85b0-bead6c9a390d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_a9795ccd-01f8-464a-85b0-bead6c9a390d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_a9795ccd-01f8-464a-85b0-bead6c9a390d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_a9795ccd-01f8-464a-85b0-bead6c9a390d" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_a9795ccd-01f8-464a-85b0-bead6c9a390d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_c562d8eb-0e21-4502-8d72-64a7d1c1f566" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_a9795ccd-01f8-464a-85b0-bead6c9a390d" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_c562d8eb-0e21-4502-8d72-64a7d1c1f566" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_49c0f714-5860-496e-a81c-9335f89dc1ea" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_c562d8eb-0e21-4502-8d72-64a7d1c1f566" xlink:to="loc_us-gaap_SubsequentEventMember_49c0f714-5860-496e-a81c-9335f89dc1ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_39e452f5-fc9c-4489-b62e-5e0f6824c645" xlink:href="https://xbrl.sec.gov/dei/2021/dei-2021.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64f13c9d-16e3-4a71-b53b-bc7405d272c4" xlink:to="loc_dei_LegalEntityAxis_39e452f5-fc9c-4489-b62e-5e0f6824c645" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_39e452f5-fc9c-4489-b62e-5e0f6824c645_default" xlink:href="https://xbrl.sec.gov/dei/2021/dei-2021.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_39e452f5-fc9c-4489-b62e-5e0f6824c645" xlink:to="loc_dei_EntityDomain_39e452f5-fc9c-4489-b62e-5e0f6824c645_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_bf817aa4-b1de-4f3f-8d12-9dd493fe4672" xlink:href="https://xbrl.sec.gov/dei/2021/dei-2021.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_39e452f5-fc9c-4489-b62e-5e0f6824c645" xlink:to="loc_dei_EntityDomain_bf817aa4-b1de-4f3f-8d12-9dd493fe4672" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_HydroChemPSCMember_2885873a-8402-4a9f-9c97-a946203d6abc" xlink:href="clh-20210630.xsd#clh_HydroChemPSCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_bf817aa4-b1de-4f3f-8d12-9dd493fe4672" xlink:to="loc_clh_HydroChemPSCMember_2885873a-8402-4a9f-9c97-a946203d6abc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/INVENTORIESANDSUPPLIESDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#INVENTORIESANDSUPPLIESDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/INVENTORIESANDSUPPLIESDetails" xlink:type="extended" id="ic96664bc6ae74ee2be232badec7e7678_INVENTORIESANDSUPPLIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryLineItems_3f8a0c1a-1cc3-4b23-ac2a-89b5c76a2aff" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InventoryLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_05a79e2b-e481-4f50-9711-a880cf271554" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InventoryNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryLineItems_3f8a0c1a-1cc3-4b23-ac2a-89b5c76a2aff" xlink:to="loc_us-gaap_InventoryNet_05a79e2b-e481-4f50-9711-a880cf271554" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryCurrentTable_6e17e6ba-da1a-482e-8333-147107c9c16a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InventoryCurrentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_InventoryLineItems_3f8a0c1a-1cc3-4b23-ac2a-89b5c76a2aff" xlink:to="loc_us-gaap_InventoryCurrentTable_6e17e6ba-da1a-482e-8333-147107c9c16a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryAxis_e94ce8e8-375a-4e06-80fc-418e428d0f1b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventoryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_InventoryCurrentTable_6e17e6ba-da1a-482e-8333-147107c9c16a" xlink:to="loc_us-gaap_PublicUtilitiesInventoryAxis_e94ce8e8-375a-4e06-80fc-418e428d0f1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_e94ce8e8-375a-4e06-80fc-418e428d0f1b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_e94ce8e8-375a-4e06-80fc-418e428d0f1b" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_e94ce8e8-375a-4e06-80fc-418e428d0f1b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_e94ce8e8-375a-4e06-80fc-418e428d0f1b" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_OilAndOilRelatedProductsMember_cb60365c-fe4a-4bad-b06b-9e9e715230a8" xlink:href="clh-20210630.xsd#clh_OilAndOilRelatedProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:to="loc_clh_OilAndOilRelatedProductsMember_cb60365c-fe4a-4bad-b06b-9e9e715230a8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventorySuppliesMember_65d7a151-bea8-4c74-9960-128c075e860d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventorySuppliesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:to="loc_us-gaap_PublicUtilitiesInventorySuppliesMember_65d7a151-bea8-4c74-9960-128c075e860d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SolventAndSolutionsMember_39418d63-077c-4cb8-9c75-8dac5d0d736d" xlink:href="clh-20210630.xsd#clh_SolventAndSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:to="loc_clh_SolventAndSolutionsMember_39418d63-077c-4cb8-9c75-8dac5d0d736d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_OtherInventoriesMember_5b2bbb04-8545-43f1-b6ea-a9dde561a9af" xlink:href="clh-20210630.xsd#clh_OtherInventoriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_272b78d8-6db9-47dd-b953-5fa94997dad7" xlink:to="loc_clh_OtherInventoriesMember_5b2bbb04-8545-43f1-b6ea-a9dde561a9af" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/PROPERTYPLANTANDEQUIPMENTScheduleofPropertyPlantandEquipmentDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#PROPERTYPLANTANDEQUIPMENTScheduleofPropertyPlantandEquipmentDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/PROPERTYPLANTANDEQUIPMENTScheduleofPropertyPlantandEquipmentDetails" xlink:type="extended" id="ic31466cc16944be2a0c29e0e9feebebf_PROPERTYPLANTANDEQUIPMENTScheduleofPropertyPlantandEquipmentDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_03c8493d-0ed3-412a-9e35-1efb0e9d074e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_03c8493d-0ed3-412a-9e35-1efb0e9d074e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_c9e80974-11c8-4283-bf08-9418161becbe" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_c9e80974-11c8-4283-bf08-9418161becbe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_b8f11600-4c87-40ad-b7b6-a577320aaa71" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_b8f11600-4c87-40ad-b7b6-a577320aaa71" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization_40e29f43-cfcd-42f0-a850-f4b0ff96551e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization_40e29f43-cfcd-42f0-a850-f4b0ff96551e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_85264f10-1f5e-4a8f-b285-f3eec3f0ead6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_70fa8d66-1217-4445-9f33-563f934ef035" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_85264f10-1f5e-4a8f-b285-f3eec3f0ead6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_b181c676-3814-4cb1-9e99-8f2422fade82" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_85264f10-1f5e-4a8f-b285-f3eec3f0ead6" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_b181c676-3814-4cb1-9e99-8f2422fade82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_b181c676-3814-4cb1-9e99-8f2422fade82_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_b181c676-3814-4cb1-9e99-8f2422fade82" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_b181c676-3814-4cb1-9e99-8f2422fade82_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_b181c676-3814-4cb1-9e99-8f2422fade82" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandMember_b9ee738c-346c-483d-ad9d-37d8f33f5ca9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LandMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_LandMember_b9ee738c-346c-483d-ad9d-37d8f33f5ca9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationCostsMember_ff77d783-4ce6-4735-ae93-9c9197cd9aa7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_AssetRetirementObligationCostsMember_ff77d783-4ce6-4735-ae93-9c9197cd9aa7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandfillMember_ec9f66f3-0f71-4d73-aa0e-13e418a9cce4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LandfillMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_LandfillMember_ec9f66f3-0f71-4d73-aa0e-13e418a9cce4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_BuildingsAndImprovemensMember_cb6c2c89-874c-4ee2-83ab-08e2a15c0ac8" xlink:href="clh-20210630.xsd#clh_BuildingsAndImprovemensMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_clh_BuildingsAndImprovemensMember_cb6c2c89-874c-4ee2-83ab-08e2a15c0ac8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_CampEquipmentMember_3054f783-708b-4e63-8d03-0991bde7b11a" xlink:href="clh-20210630.xsd#clh_CampEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_clh_CampEquipmentMember_3054f783-708b-4e63-8d03-0991bde7b11a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VehiclesMember_605052f7-3c40-4f7d-a2a4-38115cd4bbd4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_VehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_VehiclesMember_605052f7-3c40-4f7d-a2a4-38115cd4bbd4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentMember_908859c5-572f-4463-b429-6609d234bc6d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_EquipmentMember_908859c5-572f-4463-b429-6609d234bc6d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_4f41589c-e8e3-43ac-b744-f187f2c5d84a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_4f41589c-e8e3-43ac-b744-f187f2c5d84a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionInProgressMember_6faa9f1f-33ee-4142-9c4e-40a4384d1ef6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ConstructionInProgressMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd02dc6c-0c21-48e1-8546-4e2ecdc2c10a" xlink:to="loc_us-gaap_ConstructionInProgressMember_6faa9f1f-33ee-4142-9c4e-40a4384d1ef6" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSChangestoGoodwillDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#GOODWILLANDOTHERINTANGIBLEASSETSChangestoGoodwillDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSChangestoGoodwillDetails" xlink:type="extended" id="iceca2e7eec014fc3bf0ee1bb79a275bb_GOODWILLANDOTHERINTANGIBLEASSETSChangestoGoodwillDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_6ed7d38d-8dde-43d8-bb65-fa4b1376086f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_a6be3aba-1027-4b3f-9a8e-a04cc6ccb205" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_6ed7d38d-8dde-43d8-bb65-fa4b1376086f" xlink:to="loc_us-gaap_GoodwillRollForward_a6be3aba-1027-4b3f-9a8e-a04cc6ccb205" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_710c9b47-b633-4563-a6f6-b7a85a3dbf16" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a6be3aba-1027-4b3f-9a8e-a04cc6ccb205" xlink:to="loc_us-gaap_Goodwill_710c9b47-b633-4563-a6f6-b7a85a3dbf16" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_37cb57a6-4492-4f36-a342-836c5f424298" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillAcquiredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a6be3aba-1027-4b3f-9a8e-a04cc6ccb205" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_37cb57a6-4492-4f36-a342-836c5f424298" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_36d29b64-8b53-41e4-81cb-b72676610b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a6be3aba-1027-4b3f-9a8e-a04cc6ccb205" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_36d29b64-8b53-41e4-81cb-b72676610b3a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_5c895d6a-0640-413b-ba32-a45a32be9534" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Goodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_52f802be-966a-41ee-b17f-7864b96645d3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_6ed7d38d-8dde-43d8-bb65-fa4b1376086f" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_52f802be-966a-41ee-b17f-7864b96645d3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_61b77c6d-68fd-4a1e-9556-9d2b51ab991b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_52f802be-966a-41ee-b17f-7864b96645d3" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_61b77c6d-68fd-4a1e-9556-9d2b51ab991b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_61b77c6d-68fd-4a1e-9556-9d2b51ab991b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_61b77c6d-68fd-4a1e-9556-9d2b51ab991b" xlink:to="loc_us-gaap_SegmentDomain_61b77c6d-68fd-4a1e-9556-9d2b51ab991b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_3e04bdda-1c4a-4f0c-9df9-00e1ddb84dcb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_61b77c6d-68fd-4a1e-9556-9d2b51ab991b" xlink:to="loc_us-gaap_SegmentDomain_3e04bdda-1c4a-4f0c-9df9-00e1ddb84dcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_94864c44-1458-4418-8f8e-08c0cc59954a" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3e04bdda-1c4a-4f0c-9df9-00e1ddb84dcb" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_94864c44-1458-4418-8f8e-08c0cc59954a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_92adccf5-ecf3-4621-aaac-26915882de7e" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3e04bdda-1c4a-4f0c-9df9-00e1ddb84dcb" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_92adccf5-ecf3-4621-aaac-26915882de7e" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSFinitelivedandIndefiniteLivedIntangibleAssetsDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#GOODWILLANDOTHERINTANGIBLEASSETSFinitelivedandIndefiniteLivedIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSFinitelivedandIndefiniteLivedIntangibleAssetsDetails" xlink:type="extended" id="i053779d2d2524e06b98626b2d5451290_GOODWILLANDOTHERINTANGIBLEASSETSFinitelivedandIndefiniteLivedIntangibleAssetsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:href="clh-20210630.xsd#clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_d4d6882d-c516-4496-80d3-5e6facc84517" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_d4d6882d-c516-4496-80d3-5e6facc84517" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_34b49f23-92ab-4bc6-a1a3-fae5d091184f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_34b49f23-92ab-4bc6-a1a3-fae5d091184f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_d790ad49-0367-4a48-a993-3a9f61926a7e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_d790ad49-0367-4a48-a993-3a9f61926a7e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_7c8192f8-7d41-40c7-9974-f8b3ff8e864e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_7c8192f8-7d41-40c7-9974-f8b3ff8e864e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_5226ddc7-e51a-4756-88c6-7ede57a16889" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_5226ddc7-e51a-4756-88c6-7ede57a16889" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_3da337e7-c772-4c85-a2cf-9dafd3d2a412" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_3da337e7-c772-4c85-a2cf-9dafd3d2a412" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable_03f10f4e-07ca-495f-a800-77075061592a" xlink:href="clh-20210630.xsd#clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems_3616ae3d-cad3-48a1-966f-42c613d20e3f" xlink:to="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable_03f10f4e-07ca-495f-a800-77075061592a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b4740c59-aca5-4e24-9fc1-36af70b0bcd6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable_03f10f4e-07ca-495f-a800-77075061592a" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b4740c59-aca5-4e24-9fc1-36af70b0bcd6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_b4740c59-aca5-4e24-9fc1-36af70b0bcd6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b4740c59-aca5-4e24-9fc1-36af70b0bcd6" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_b4740c59-aca5-4e24-9fc1-36af70b0bcd6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_637a16d5-b5f4-44b7-aca0-5df883035a99" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b4740c59-aca5-4e24-9fc1-36af70b0bcd6" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_637a16d5-b5f4-44b7-aca0-5df883035a99" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_PermitsMember_9845142a-2009-4b71-a77c-e904025d1eeb" xlink:href="clh-20210630.xsd#clh_PermitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_637a16d5-b5f4-44b7-aca0-5df883035a99" xlink:to="loc_clh_PermitsMember_9845142a-2009-4b71-a77c-e904025d1eeb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_24c9b845-27ae-40e2-a053-bc0c8ddf155a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_637a16d5-b5f4-44b7-aca0-5df883035a99" xlink:to="loc_us-gaap_CustomerRelationshipsMember_24c9b845-27ae-40e2-a053-bc0c8ddf155a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIntangibleAssetsMember_83cd9c09-3a96-41fb-8b5d-cb945b083847" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_637a16d5-b5f4-44b7-aca0-5df883035a99" xlink:to="loc_us-gaap_OtherIntangibleAssetsMember_83cd9c09-3a96-41fb-8b5d-cb945b083847" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_1fb85e3a-de65-416f-824f-0c52585e2d1a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_clh_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable_03f10f4e-07ca-495f-a800-77075061592a" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_1fb85e3a-de65-416f-824f-0c52585e2d1a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_1fb85e3a-de65-416f-824f-0c52585e2d1a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_1fb85e3a-de65-416f-824f-0c52585e2d1a" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_1fb85e3a-de65-416f-824f-0c52585e2d1a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_ddf12d9b-7691-4717-aa83-fd11fe908c90" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_1fb85e3a-de65-416f-824f-0c52585e2d1a" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_ddf12d9b-7691-4717-aa83-fd11fe908c90" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_31f18d1a-67af-4406-98ff-65ff08134efa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_TrademarksAndTradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_ddf12d9b-7691-4717-aa83-fd11fe908c90" xlink:to="loc_us-gaap_TrademarksAndTradeNamesMember_31f18d1a-67af-4406-98ff-65ff08134efa" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSAdditionalInformationDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#GOODWILLANDOTHERINTANGIBLEASSETSAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/GOODWILLANDOTHERINTANGIBLEASSETSAdditionalInformationDetails" xlink:type="extended" id="iaedb8abfa5c74b35b50e55ca6cc99735_GOODWILLANDOTHERINTANGIBLEASSETSAdditionalInformationDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportingUnits_8b6d4c04-e38a-4640-90cc-42c2c1fafe5f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NumberOfReportingUnits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:to="loc_us-gaap_NumberOfReportingUnits_8b6d4c04-e38a-4640-90cc-42c2c1fafe5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_523585cd-56d9-404d-baef-3b5bfefec9d3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_523585cd-56d9-404d-baef-3b5bfefec9d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_600bbfbf-7512-4c4a-a275-f214b49439db" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_600bbfbf-7512-4c4a-a275-f214b49439db" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_FiniteLivedIntangibleAssetsWrittenOff_37bc9bf7-f751-4584-8c16-e708407b1c14" xlink:href="clh-20210630.xsd#clh_FiniteLivedIntangibleAssetsWrittenOff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:to="loc_clh_FiniteLivedIntangibleAssetsWrittenOff_37bc9bf7-f751-4584-8c16-e708407b1c14" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_3c447ac6-a368-4cb6-95e8-7e1570138eb0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_d43c336b-256c-4606-8789-968d73923e3f" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_3c447ac6-a368-4cb6-95e8-7e1570138eb0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_6d9523c9-c807-41bd-99a2-7d273cdae5fe" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_3c447ac6-a368-4cb6-95e8-7e1570138eb0" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_6d9523c9-c807-41bd-99a2-7d273cdae5fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_6d9523c9-c807-41bd-99a2-7d273cdae5fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_6d9523c9-c807-41bd-99a2-7d273cdae5fe" xlink:to="loc_us-gaap_SegmentDomain_6d9523c9-c807-41bd-99a2-7d273cdae5fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_aca9a2cb-d343-4eac-8672-a8b897796f3b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_6d9523c9-c807-41bd-99a2-7d273cdae5fe" xlink:to="loc_us-gaap_SegmentDomain_aca9a2cb-d343-4eac-8672-a8b897796f3b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_dce4bb43-da72-4522-b144-77ce59b6d59a" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_aca9a2cb-d343-4eac-8672-a8b897796f3b" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_dce4bb43-da72-4522-b144-77ce59b6d59a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_3cdc1a90-1587-4ae4-82e9-1694c99cb9d5" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_aca9a2cb-d343-4eac-8672-a8b897796f3b" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_3cdc1a90-1587-4ae4-82e9-1694c99cb9d5" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/CLOSUREANDPOSTCLOSURELIABILITIESChangesinPostClosureLiabilitiesDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#CLOSUREANDPOSTCLOSURELIABILITIESChangesinPostClosureLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/CLOSUREANDPOSTCLOSURELIABILITIESChangesinPostClosureLiabilitiesDetails" xlink:type="extended" id="i769b4ce716de416aa3d3d458960d1b07_CLOSUREANDPOSTCLOSURELIABILITIESChangesinPostClosureLiabilitiesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_clh_ClosureAndPostClosureLiabilitiesLineItems_4a9fe87b-fedb-4220-af5e-d61a27f73513" xlink:href="clh-20210630.xsd#clh_ClosureAndPostClosureLiabilitiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesLineItems_4a9fe87b-fedb-4220-af5e-d61a27f73513" xlink:to="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligation_97ba15ce-469f-4be8-b602-90fbdada6b3e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_us-gaap_AssetRetirementObligation_97ba15ce-469f-4be8-b602-90fbdada6b3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AssetRetirementObligationLiabilitiesAssumedInAcquisition_9837b24a-e92a-4eda-81cd-f7b376d054cf" xlink:href="clh-20210630.xsd#clh_AssetRetirementObligationLiabilitiesAssumedInAcquisition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_clh_AssetRetirementObligationLiabilitiesAssumedInAcquisition_9837b24a-e92a-4eda-81cd-f7b376d054cf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationLiabilitiesIncurred_fa27ac8a-88d0-4d06-8459-b9551323b39b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationLiabilitiesIncurred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_us-gaap_AssetRetirementObligationLiabilitiesIncurred_fa27ac8a-88d0-4d06-8459-b9551323b39b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationAccretionExpense_ef6bc7cc-9446-4ae6-81f4-ebcb2c1f98cc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationAccretionExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_us-gaap_AssetRetirementObligationAccretionExpense_ef6bc7cc-9446-4ae6-81f4-ebcb2c1f98cc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AssetRetirementObligationChangesRecordedInStatementOfIncome_bd366269-2d85-4fc9-9d1b-fbbd6e1d6ce1" xlink:href="clh-20210630.xsd#clh_AssetRetirementObligationChangesRecordedInStatementOfIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_clh_AssetRetirementObligationChangesRecordedInStatementOfIncome_bd366269-2d85-4fc9-9d1b-fbbd6e1d6ce1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AssetRetirementObligationChangesRecordedInBalanceSheet_874a591e-201e-4866-bb6f-09f45a374bd5" xlink:href="clh-20210630.xsd#clh_AssetRetirementObligationChangesRecordedInBalanceSheet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_clh_AssetRetirementObligationChangesRecordedInBalanceSheet_874a591e-201e-4866-bb6f-09f45a374bd5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AssetRetirementObligationPayments_24acfb4f-3911-4848-a763-f231da77e61a" xlink:href="clh-20210630.xsd#clh_AssetRetirementObligationPayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_clh_AssetRetirementObligationPayments_24acfb4f-3911-4848-a763-f231da77e61a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationForeignCurrencyTranslationGainLoss_f2174c40-6ba2-4665-ba53-0ea0aec95941" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward_bf547743-74a8-49aa-88e1-e009b6052a47" xlink:to="loc_us-gaap_AssetRetirementObligationForeignCurrencyTranslationGainLoss_f2174c40-6ba2-4665-ba53-0ea0aec95941" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligation_060acf1f-ed6a-4066-9f69-0488b4c09944" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligation"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ClosureAndPostClosureLiabilitiesTable_610fca94-9166-40de-accb-e118eaeceeaa" xlink:href="clh-20210630.xsd#clh_ClosureAndPostClosureLiabilitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesLineItems_4a9fe87b-fedb-4220-af5e-d61a27f73513" xlink:to="loc_clh_ClosureAndPostClosureLiabilitiesTable_610fca94-9166-40de-accb-e118eaeceeaa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ClosureAndPostClosureLiabilitiesAxis_179d9839-ba75-40eb-b91a-fdfe57828f27" xlink:href="clh-20210630.xsd#clh_ClosureAndPostClosureLiabilitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesTable_610fca94-9166-40de-accb-e118eaeceeaa" xlink:to="loc_clh_ClosureAndPostClosureLiabilitiesAxis_179d9839-ba75-40eb-b91a-fdfe57828f27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ClosureAndPostClosureLiabilitiesDomain_179d9839-ba75-40eb-b91a-fdfe57828f27_default" xlink:href="clh-20210630.xsd#clh_ClosureAndPostClosureLiabilitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesAxis_179d9839-ba75-40eb-b91a-fdfe57828f27" xlink:to="loc_clh_ClosureAndPostClosureLiabilitiesDomain_179d9839-ba75-40eb-b91a-fdfe57828f27_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ClosureAndPostClosureLiabilitiesDomain_599ad939-8040-40c8-b210-457a64a11ad7" xlink:href="clh-20210630.xsd#clh_ClosureAndPostClosureLiabilitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesAxis_179d9839-ba75-40eb-b91a-fdfe57828f27" xlink:to="loc_clh_ClosureAndPostClosureLiabilitiesDomain_599ad939-8040-40c8-b210-457a64a11ad7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_LandfillRetirementLiabilityMember_6992744e-20b8-418e-8e7c-7f496d94b5f7" xlink:href="clh-20210630.xsd#clh_LandfillRetirementLiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesDomain_599ad939-8040-40c8-b210-457a64a11ad7" xlink:to="loc_clh_LandfillRetirementLiabilityMember_6992744e-20b8-418e-8e7c-7f496d94b5f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NonLandfillRetirementLiabilityMember_a8e2ab08-1a3b-4522-820e-7f33f6d7c7e7" xlink:href="clh-20210630.xsd#clh_NonLandfillRetirementLiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ClosureAndPostClosureLiabilitiesDomain_599ad939-8040-40c8-b210-457a64a11ad7" xlink:to="loc_clh_NonLandfillRetirementLiabilityMember_a8e2ab08-1a3b-4522-820e-7f33f6d7c7e7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/REMEDIALLIABILITIESDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#REMEDIALLIABILITIESDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/REMEDIALLIABILITIESDetails" xlink:type="extended" id="i0b43a026bf504ae0857b914c172bb7ca_REMEDIALLIABILITIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SiteContingencyLineItems_b15c9ff5-c130-4de4-8f92-e87887184c9b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SiteContingencyLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SiteContingencyLineItems_b15c9ff5-c130-4de4-8f92-e87887184c9b" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_c12f606f-3dd3-47ad-a087-594ad886f4d6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingencies_c12f606f-3dd3-47ad-a087-594ad886f4d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses_bcaf1ec3-ab10-4611-9f7b-18a279c7af6b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses_bcaf1ec3-ab10-4611-9f7b-18a279c7af6b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForRevisionInEstimates_580c962e-2256-4fc1-876e-4227b4eaca97" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForRevisionInEstimates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForRevisionInEstimates_580c962e-2256-4fc1-876e-4227b4eaca97" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_f0cadc2e-7845-4613-8e38-aed786ae90ad" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesPayments1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_f0cadc2e-7845-4613-8e38-aed786ae90ad" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForCurrencyTranslationAndOther_04737afd-eeab-417f-9680-64ac1ee58c60" xlink:href="clh-20210630.xsd#clh_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForCurrencyTranslationAndOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesRollForward_4fc8b3c3-5b4d-47b0-a3bf-1d7c1cd0afad" xlink:to="loc_clh_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForCurrencyTranslationAndOther_04737afd-eeab-417f-9680-64ac1ee58c60" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_82dd5d95-d4fb-4f85-a259-ed5ff2bf7626" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingencies"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SiteContingencyTable_68ea71de-90b0-41eb-9e8a-a0344013f332" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SiteContingencyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SiteContingencyLineItems_b15c9ff5-c130-4de4-8f92-e87887184c9b" xlink:to="loc_us-gaap_SiteContingencyTable_68ea71de-90b0-41eb-9e8a-a0344013f332" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteAxis_7adfa304-567d-417d-8ea8-55e6d1e6b81c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SiteContingencyTable_68ea71de-90b0-41eb-9e8a-a0344013f332" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteAxis_7adfa304-567d-417d-8ea8-55e6d1e6b81c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_7adfa304-567d-417d-8ea8-55e6d1e6b81c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_7adfa304-567d-417d-8ea8-55e6d1e6b81c" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_7adfa304-567d-417d-8ea8-55e6d1e6b81c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_b2fb0b00-7a89-4043-b469-8a6ffbed4fe1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_7adfa304-567d-417d-8ea8-55e6d1e6b81c" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_b2fb0b00-7a89-4043-b469-8a6ffbed4fe1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_RemedialLiabilitiesForLandfillSitesMember_b46665e7-b734-4db5-980b-52f41e692617" xlink:href="clh-20210630.xsd#clh_RemedialLiabilitiesForLandfillSitesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_b2fb0b00-7a89-4043-b469-8a6ffbed4fe1" xlink:to="loc_clh_RemedialLiabilitiesForLandfillSitesMember_b46665e7-b734-4db5-980b-52f41e692617" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_RemedialLiabilitiesForInactiveSitesMember_8a757b44-0f59-4a54-a8a6-1c0b2a1f4080" xlink:href="clh-20210630.xsd#clh_RemedialLiabilitiesForInactiveSitesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_b2fb0b00-7a89-4043-b469-8a6ffbed4fe1" xlink:to="loc_clh_RemedialLiabilitiesForInactiveSitesMember_8a757b44-0f59-4a54-a8a6-1c0b2a1f4080" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_RemedialLiabilitiesIncludingSuperfundForNonLandfillOperationsMember_93d97dae-3181-4abf-b754-ea9dc5ef9951" xlink:href="clh-20210630.xsd#clh_RemedialLiabilitiesIncludingSuperfundForNonLandfillOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_b2fb0b00-7a89-4043-b469-8a6ffbed4fe1" xlink:to="loc_clh_RemedialLiabilitiesIncludingSuperfundForNonLandfillOperationsMember_93d97dae-3181-4abf-b754-ea9dc5ef9951" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/FINANCINGARRANGEMENTSSummaryofFinancingArrangementsDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#FINANCINGARRANGEMENTSSummaryofFinancingArrangementsDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/FINANCINGARRANGEMENTSSummaryofFinancingArrangementsDetails" xlink:type="extended" id="i0d7423e638b245cdb8f4e9bd11d3e0ca_FINANCINGARRANGEMENTSSummaryofFinancingArrangementsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_6e954851-46bd-46dc-be5a-ee6670851fcb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_LongTermDebtCurrent_6e954851-46bd-46dc-be5a-ee6670851fcb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_6df205bf-c46b-4ec0-8aa4-aaea7a0bc388" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_6df205bf-c46b-4ec0-8aa4-aaea7a0bc388" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_23a3cc7a-16f5-42ed-9045-577961e2d480" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_23a3cc7a-16f5-42ed-9045-577961e2d480" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_5b38d9b7-ef92-48c8-840b-9be169fadc38" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_5b38d9b7-ef92-48c8-840b-9be169fadc38" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_54e17bb8-7f7f-4b64-9465-60bd765cf36d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_54e17bb8-7f7f-4b64-9465-60bd765cf36d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_d0918687-4658-4d34-bea7-3016c414b79e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7b1203d7-f947-464c-8396-38f56b0f5246" xlink:to="loc_us-gaap_DebtInstrumentTable_d0918687-4658-4d34-bea7-3016c414b79e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_0ec333b9-11fa-4fe2-abf8-525ad5441579" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d0918687-4658-4d34-bea7-3016c414b79e" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_0ec333b9-11fa-4fe2-abf8-525ad5441579" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_0ec333b9-11fa-4fe2-abf8-525ad5441579_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_0ec333b9-11fa-4fe2-abf8-525ad5441579" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_0ec333b9-11fa-4fe2-abf8-525ad5441579_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_87884411-63a2-4ddb-b4bc-7b39b63c68ce" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_0ec333b9-11fa-4fe2-abf8-525ad5441579" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_87884411-63a2-4ddb-b4bc-7b39b63c68ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_08dd502f-91a2-4a56-b098-1bf6d35842b3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_87884411-63a2-4ddb-b4bc-7b39b63c68ce" xlink:to="loc_us-gaap_SecuredDebtMember_08dd502f-91a2-4a56-b098-1bf6d35842b3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnsecuredDebtMember_27a79972-0321-4f22-8573-83afd5e0dd8e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_UnsecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_87884411-63a2-4ddb-b4bc-7b39b63c68ce" xlink:to="loc_us-gaap_UnsecuredDebtMember_27a79972-0321-4f22-8573-83afd5e0dd8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d0918687-4658-4d34-bea7-3016c414b79e" xlink:to="loc_us-gaap_DebtInstrumentAxis_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1672c3dc-f8db-412c-92bb-19863e0dd984" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_1f82edd2-53ac-46c7-8a29-3b4ab6e3cfc3" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1672c3dc-f8db-412c-92bb-19863e0dd984" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_TermLoanAgreementMember_e5514290-2755-4827-b001-2d24f7bc0bed" xlink:href="clh-20210630.xsd#clh_TermLoanAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1672c3dc-f8db-412c-92bb-19863e0dd984" xlink:to="loc_clh_TermLoanAgreementMember_e5514290-2755-4827-b001-2d24f7bc0bed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SeniorUnsecuredNotesdue2027Member_71bfedba-2712-4c21-a01d-cde4efd7e93a" xlink:href="clh-20210630.xsd#clh_SeniorUnsecuredNotesdue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1672c3dc-f8db-412c-92bb-19863e0dd984" xlink:to="loc_clh_SeniorUnsecuredNotesdue2027Member_71bfedba-2712-4c21-a01d-cde4efd7e93a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SeniorUnsecuredNotesdue2029Member_44925980-c781-4a9c-863d-bc28efb9943e" xlink:href="clh-20210630.xsd#clh_SeniorUnsecuredNotesdue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1672c3dc-f8db-412c-92bb-19863e0dd984" xlink:to="loc_clh_SeniorUnsecuredNotesdue2029Member_44925980-c781-4a9c-863d-bc28efb9943e" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/FINANCINGARRANGEMENTSAdditionalInformationDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#FINANCINGARRANGEMENTSAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/FINANCINGARRANGEMENTSAdditionalInformationDetails" xlink:type="extended" id="i5220422b887c48d9aa91c05c3c2e496e_FINANCINGARRANGEMENTSAdditionalInformationDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_ce852a09-96d2-4266-a2e0-2421d766434d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LongTermDebtFairValue_ce852a09-96d2-4266-a2e0-2421d766434d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_6d514919-c86f-436c-9e65-4c49880977f0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_6d514919-c86f-436c-9e65-4c49880977f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_63acbff1-4367-4130-abc4-8d3fc34d4f84" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LineOfCredit_63acbff1-4367-4130-abc4-8d3fc34d4f84" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_6c10b3b3-768d-49d0-8427-6cbc171fb086" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_6c10b3b3-768d-49d0-8427-6cbc171fb086" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_5ed0d116-84f5-4e35-b9ed-32705dcc57a5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_5ed0d116-84f5-4e35-b9ed-32705dcc57a5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_bd0373da-f269-4b24-9789-7f3031a89910" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_LongTermDebt_bd0373da-f269-4b24-9789-7f3031a89910" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_88fd850b-3fe9-4df7-8221-59bd4d9d1e28" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_DerivativeNotionalAmount_88fd850b-3fe9-4df7-8221-59bd4d9d1e28" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_09bdd2a6-acab-4dc6-a91e-ad1771e2a3a4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_09bdd2a6-acab-4dc6-a91e-ad1771e2a3a4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_e4a3dcbe-cd66-4936-a255-a96c17f09131" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_e4a3dcbe-cd66-4936-a255-a96c17f09131" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue_23ee54ad-a164-4da4-945f-f4915bdfa5de" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue_23ee54ad-a164-4da4-945f-f4915bdfa5de" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c2dbf12e-fa7b-494d-a1f0-67fefdcb7317" xlink:to="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_b03aea24-3166-490c-aba2-6f580cbebcd6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:to="loc_us-gaap_CreditFacilityAxis_b03aea24-3166-490c-aba2-6f580cbebcd6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_b03aea24-3166-490c-aba2-6f580cbebcd6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_b03aea24-3166-490c-aba2-6f580cbebcd6" xlink:to="loc_us-gaap_CreditFacilityDomain_b03aea24-3166-490c-aba2-6f580cbebcd6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_6c7dca2b-afb5-4f3d-badf-a1ffc12a7a92" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_b03aea24-3166-490c-aba2-6f580cbebcd6" xlink:to="loc_us-gaap_CreditFacilityDomain_6c7dca2b-afb5-4f3d-badf-a1ffc12a7a92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_cc627fb8-1f4e-490d-b24d-6a6d1f422014" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_6c7dca2b-afb5-4f3d-badf-a1ffc12a7a92" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_cc627fb8-1f4e-490d-b24d-6a6d1f422014" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_ea5a3789-6828-45ea-b74e-411630953b31" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_aaf51cf8-2203-4ebc-856d-c5e4c22f3b06" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_ea5a3789-6828-45ea-b74e-411630953b31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_a77be97c-8ff5-471d-9133-9b9fb1aa63ea" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_ea5a3789-6828-45ea-b74e-411630953b31" xlink:to="loc_us-gaap_LineOfCreditMember_a77be97c-8ff5-471d-9133-9b9fb1aa63ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_8ec8b99e-cb7a-4a9e-b809-257d773f3df0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:to="loc_us-gaap_DebtInstrumentAxis_8ec8b99e-cb7a-4a9e-b809-257d773f3df0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8ec8b99e-cb7a-4a9e-b809-257d773f3df0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_8ec8b99e-cb7a-4a9e-b809-257d773f3df0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8ec8b99e-cb7a-4a9e-b809-257d773f3df0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_19628e5a-4675-4f48-950f-ec9bc00b65f3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_8ec8b99e-cb7a-4a9e-b809-257d773f3df0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_19628e5a-4675-4f48-950f-ec9bc00b65f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_TermLoanswithInterestRateSwapAgreementsMember_25715f7a-e840-4125-97a5-faf521edbfef" xlink:href="clh-20210630.xsd#clh_TermLoanswithInterestRateSwapAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_19628e5a-4675-4f48-950f-ec9bc00b65f3" xlink:to="loc_clh_TermLoanswithInterestRateSwapAgreementsMember_25715f7a-e840-4125-97a5-faf521edbfef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_1eb0a5f7-8485-403e-a625-579cf7a4dcfe" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5033a3e2-3b61-4226-b05e-667035189cca" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_1eb0a5f7-8485-403e-a625-579cf7a4dcfe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_1eb0a5f7-8485-403e-a625-579cf7a4dcfe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1eb0a5f7-8485-403e-a625-579cf7a4dcfe" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_1eb0a5f7-8485-403e-a625-579cf7a4dcfe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_d21eb369-9b20-4414-89c3-099f8906956c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1eb0a5f7-8485-403e-a625-579cf7a4dcfe" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_d21eb369-9b20-4414-89c3-099f8906956c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_13d239a6-14e7-405e-a0d7-f4f0e53f70b5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_d21eb369-9b20-4414-89c3-099f8906956c" xlink:to="loc_us-gaap_InterestRateSwapMember_13d239a6-14e7-405e-a0d7-f4f0e53f70b5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/EARNINGSPERSHAREAntiDilutiveSecuritiesDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#EARNINGSPERSHAREAntiDilutiveSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/EARNINGSPERSHAREAntiDilutiveSecuritiesDetails" xlink:type="extended" id="i382f363e207e4ee9aca80e98705db637_EARNINGSPERSHAREAntiDilutiveSecuritiesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_240ec0cc-ea30-42e0-aa97-7811c3498d54" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_8fdc0774-5b1d-417e-80bd-252370029cd9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_240ec0cc-ea30-42e0-aa97-7811c3498d54" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_8fdc0774-5b1d-417e-80bd-252370029cd9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfPerformanceStockAwardsThatPerformanceCriteriaNotAttained_09cea2dc-3fc8-4b6c-992a-e4114c006d9f" xlink:href="clh-20210630.xsd#clh_NumberOfPerformanceStockAwardsThatPerformanceCriteriaNotAttained"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_240ec0cc-ea30-42e0-aa97-7811c3498d54" xlink:to="loc_clh_NumberOfPerformanceStockAwardsThatPerformanceCriteriaNotAttained_09cea2dc-3fc8-4b6c-992a-e4114c006d9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_34e3fc7d-7532-400c-989f-a6427e7974a4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_240ec0cc-ea30-42e0-aa97-7811c3498d54" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_34e3fc7d-7532-400c-989f-a6427e7974a4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1b8263c7-86d9-4260-9829-e1a03ebbfedb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_34e3fc7d-7532-400c-989f-a6427e7974a4" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1b8263c7-86d9-4260-9829-e1a03ebbfedb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1b8263c7-86d9-4260-9829-e1a03ebbfedb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1b8263c7-86d9-4260-9829-e1a03ebbfedb" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1b8263c7-86d9-4260-9829-e1a03ebbfedb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_83c366d1-b0e8-4a32-826e-75dd40cef20e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1b8263c7-86d9-4260-9829-e1a03ebbfedb" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_83c366d1-b0e8-4a32-826e-75dd40cef20e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_a0a335d9-7946-4bfa-89cf-5295e7bb7fd1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_83c366d1-b0e8-4a32-826e-75dd40cef20e" xlink:to="loc_us-gaap_RestrictedStockMember_a0a335d9-7946-4bfa-89cf-5295e7bb7fd1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_RestrictedStockAwardsAndPerformanceAwardsMember_7b51474a-6016-4ca3-947e-b98965a86fc4" xlink:href="clh-20210630.xsd#clh_RestrictedStockAwardsAndPerformanceAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_83c366d1-b0e8-4a32-826e-75dd40cef20e" xlink:to="loc_clh_RestrictedStockAwardsAndPerformanceAwardsMember_7b51474a-6016-4ca3-947e-b98965a86fc4" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/ACCUMULATEDOTHERCOMPREHENSIVELOSSChangesinAccumulatedOtherComprehensiveLossbyComponentDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#ACCUMULATEDOTHERCOMPREHENSIVELOSSChangesinAccumulatedOtherComprehensiveLossbyComponentDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/ACCUMULATEDOTHERCOMPREHENSIVELOSSChangesinAccumulatedOtherComprehensiveLossbyComponentDetails" xlink:type="extended" id="i0b5c1d3ff5184a4b94672412722a21f8_ACCUMULATEDOTHERCOMPREHENSIVELOSSChangesinAccumulatedOtherComprehensiveLossbyComponentDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_eea5ca53-d18f-41ae-b282-bd2583f897fb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_eea5ca53-d18f-41ae-b282-bd2583f897fb" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_eb11443b-91c8-49af-98ad-cd45abbe5876" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:to="loc_us-gaap_StockholdersEquity_eb11443b-91c8-49af-98ad-cd45abbe5876" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_b98e5224-b236-46d8-904b-ab544318ca10" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:to="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_b98e5224-b236-46d8-904b-ab544318ca10" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_60f1a5d2-19b7-459f-9553-e906fde757c6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_60f1a5d2-19b7-459f-9553-e906fde757c6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_1921f062-9ec4-4dfe-a61f-8b890d9206cc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_1921f062-9ec4-4dfe-a61f-8b890d9206cc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_41119c3e-c841-4bac-b586-54015bb1d20c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_f91afba1-ebda-4c80-932f-1af2408aa0b3" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_41119c3e-c841-4bac-b586-54015bb1d20c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_7f096d7a-3854-487d-81f2-eddeb7d077a2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_5625c94a-4a94-45eb-92a8-9fec744b5c28" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_eea5ca53-d18f-41ae-b282-bd2583f897fb" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_5625c94a-4a94-45eb-92a8-9fec744b5c28" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_5625c94a-4a94-45eb-92a8-9fec744b5c28" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b" xlink:to="loc_us-gaap_EquityComponentDomain_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_57bc6bc3-fb8f-44a1-8447-e851eedfcf5b" xlink:to="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_6b868099-9333-4d98-b23f-7db08daf6f6d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_6b868099-9333-4d98-b23f-7db08daf6f6d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_3b5ac740-c2c4-408e-b2c9-84fd807e5680" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_3b5ac740-c2c4-408e-b2c9-84fd807e5680" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_f91a4a23-bfae-424d-9e81-38c7a2a9b000" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_f91a4a23-bfae-424d-9e81-38c7a2a9b000" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_278191ef-8e58-4665-a8c0-ea12c2492055" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_278191ef-8e58-4665-a8c0-ea12c2492055" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_bd992353-da3f-4d80-bd33-0c9ecb36a8a0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_16fcfc0a-e392-4f80-acd1-8c581414247d" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_bd992353-da3f-4d80-bd33-0c9ecb36a8a0" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/ACCUMULATEDOTHERCOMPREHENSIVELOSSReclassifiedOutofAccumulatedOtherComprehensiveLossDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#ACCUMULATEDOTHERCOMPREHENSIVELOSSReclassifiedOutofAccumulatedOtherComprehensiveLossDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/ACCUMULATEDOTHERCOMPREHENSIVELOSSReclassifiedOutofAccumulatedOtherComprehensiveLossDetails" xlink:type="extended" id="i1ed25526eb1b48f7a44b9b154aefa460_ACCUMULATEDOTHERCOMPREHENSIVELOSSReclassifiedOutofAccumulatedOtherComprehensiveLossDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_84daf6f2-582f-4568-b5e5-237bd9b87e7c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_InterestExpenseNet_6b196724-feb0-44f8-9f35-40198fef398d" xlink:href="clh-20210630.xsd#clh_InterestExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_84daf6f2-582f-4568-b5e5-237bd9b87e7c" xlink:to="loc_clh_InterestExpenseNet_6b196724-feb0-44f8-9f35-40198fef398d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_c69f5368-ec8d-4396-aefe-2dc9e38dc57d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_84daf6f2-582f-4568-b5e5-237bd9b87e7c" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_c69f5368-ec8d-4396-aefe-2dc9e38dc57d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_cb5d5b16-f573-4f02-8592-1dae91260b94" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_c69f5368-ec8d-4396-aefe-2dc9e38dc57d" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_cb5d5b16-f573-4f02-8592-1dae91260b94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_cb5d5b16-f573-4f02-8592-1dae91260b94_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cb5d5b16-f573-4f02-8592-1dae91260b94" xlink:to="loc_us-gaap_EquityComponentDomain_cb5d5b16-f573-4f02-8592-1dae91260b94_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_a77744f3-115a-4371-b9d9-32913e872267" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cb5d5b16-f573-4f02-8592-1dae91260b94" xlink:to="loc_us-gaap_EquityComponentDomain_a77744f3-115a-4371-b9d9-32913e872267" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_be49e73b-3c38-4e31-a2e8-335fbf97c7d0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_a77744f3-115a-4371-b9d9-32913e872267" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_be49e73b-3c38-4e31-a2e8-335fbf97c7d0" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/STOCKBASEDCOMPENSATIONRestrictedStockAwardsDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#STOCKBASEDCOMPENSATIONRestrictedStockAwardsDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/STOCKBASEDCOMPENSATIONRestrictedStockAwardsDetails" xlink:type="extended" id="icc4d41c4146748a9895e8bdeb6298634_STOCKBASEDCOMPENSATIONRestrictedStockAwardsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_2846358f-b61c-4456-9bb3-5751180dfd74" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_2846358f-b61c-4456-9bb3-5751180dfd74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_7d0fce91-b78d-4bc6-8dfe-f12a93eb69ff" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_7d0fce91-b78d-4bc6-8dfe-f12a93eb69ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_de2d0a23-2331-4214-b58e-c60726d405a9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_de2d0a23-2331-4214-b58e-c60726d405a9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_172b44e5-ec6a-4ac4-81e7-ef85341b0e42" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_f966a33d-eb06-4568-b98b-b8d7d2c2be7e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_172b44e5-ec6a-4ac4-81e7-ef85341b0e42" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_b185e401-1a09-4393-93b7-09cf572480ac" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_490c7313-52c9-4a64-8991-63b07be44bae" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_490c7313-52c9-4a64-8991-63b07be44bae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_39392ed0-daef-48e4-83b9-a185a3b76e9d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_39392ed0-daef-48e4-83b9-a185a3b76e9d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c1e2c300-9e67-42d9-aba6-f13c9a3d3916" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c1e2c300-9e67-42d9-aba6-f13c9a3d3916" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_b6250367-ea23-46c2-a252-e364597df52f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6e8fce66-e939-4819-b84a-7bb4abf614e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_b6250367-ea23-46c2-a252-e364597df52f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_919c8da6-1e12-4ca2-9a93-775b2938e6b0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_ced861a6-af76-4266-9e49-173a62a8cb05" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_ced861a6-af76-4266-9e49-173a62a8cb05" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_90624f92-2f92-41aa-8743-b612a0d8d13a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_90624f92-2f92-41aa-8743-b612a0d8d13a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_87450901-e58b-4d3c-a9c1-a85240973742" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_87450901-e58b-4d3c-a9c1-a85240973742" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ca997bc6-2375-420c-9453-fde5f48ca2b7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_bef3075f-770f-4402-9b6f-d5ce754f5313" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ca997bc6-2375-420c-9453-fde5f48ca2b7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_c434f026-4280-4eb1-86e1-a73f13893696" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ca997bc6-2375-420c-9453-fde5f48ca2b7" xlink:to="loc_us-gaap_AwardTypeAxis_c434f026-4280-4eb1-86e1-a73f13893696" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c434f026-4280-4eb1-86e1-a73f13893696_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_c434f026-4280-4eb1-86e1-a73f13893696" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c434f026-4280-4eb1-86e1-a73f13893696_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1fa42ff2-3466-44cd-95be-4522b99f78e9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_c434f026-4280-4eb1-86e1-a73f13893696" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1fa42ff2-3466-44cd-95be-4522b99f78e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_6d7d3eac-4862-47d0-9f56-7c84eb174109" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1fa42ff2-3466-44cd-95be-4522b99f78e9" xlink:to="loc_us-gaap_RestrictedStockMember_6d7d3eac-4862-47d0-9f56-7c84eb174109" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/STOCKBASEDCOMPENSATIONPerformanceStockAwardsDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#STOCKBASEDCOMPENSATIONPerformanceStockAwardsDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/STOCKBASEDCOMPENSATIONPerformanceStockAwardsDetails" xlink:type="extended" id="i9746d23e7efb471d89dce613a75c5947_STOCKBASEDCOMPENSATIONPerformanceStockAwardsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_e81a385c-7deb-494f-ac93-3e234c56f151" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_e81a385c-7deb-494f-ac93-3e234c56f151" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_7d984a8a-3685-434d-abee-0b7e3ae2d8ae" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_7d984a8a-3685-434d-abee-0b7e3ae2d8ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_872f3121-3bed-48ca-aafc-bdf6f76e0ce6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_872f3121-3bed-48ca-aafc-bdf6f76e0ce6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_a75af22e-c1c4-49e2-9c4c-968e90078f34" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_841923a9-89b1-438f-8629-186307c085a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_a75af22e-c1c4-49e2-9c4c-968e90078f34" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_1251821b-3b39-4d99-a056-4eb03c1fa67b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_15a7f639-aacc-475f-a9ad-52044c8cc81a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_15a7f639-aacc-475f-a9ad-52044c8cc81a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5296014f-4ed1-45b2-be65-04544ff8747b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5296014f-4ed1-45b2-be65-04544ff8747b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_b6d9760c-8097-4ef5-8591-526f6cf1adf2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_b6d9760c-8097-4ef5-8591-526f6cf1adf2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_e35398b5-065c-4fce-a027-596f4c6106e0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_c81ea753-1ab0-4525-b878-8ccc61b88afa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_e35398b5-065c-4fce-a027-596f4c6106e0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_b3407ab2-d652-4c9b-a2e5-86632a78232c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_eed57540-6fa6-43af-a41d-ddc2c4e933e5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_eed57540-6fa6-43af-a41d-ddc2c4e933e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_824d8bb8-0082-4949-8186-bfb9dba7e13b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_824d8bb8-0082-4949-8186-bfb9dba7e13b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_2bcd2b77-2a8f-41b0-b429-47dabf2d3398" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f7e357b1-9478-48c0-be29-1fd1ec4aef77" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_2bcd2b77-2a8f-41b0-b429-47dabf2d3398" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_75b5ea02-16a8-466f-a50b-d21766ba6167" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_2bcd2b77-2a8f-41b0-b429-47dabf2d3398" xlink:to="loc_us-gaap_AwardTypeAxis_75b5ea02-16a8-466f-a50b-d21766ba6167" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_75b5ea02-16a8-466f-a50b-d21766ba6167_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_75b5ea02-16a8-466f-a50b-d21766ba6167" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_75b5ea02-16a8-466f-a50b-d21766ba6167_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_43ea1419-dcf0-4a97-be38-e3563b44e02e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_75b5ea02-16a8-466f-a50b-d21766ba6167" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_43ea1419-dcf0-4a97-be38-e3563b44e02e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_PerformanceStockAwardsMember_90558d50-0556-40a9-9091-15643827235c" xlink:href="clh-20210630.xsd#clh_PerformanceStockAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_43ea1419-dcf0-4a97-be38-e3563b44e02e" xlink:to="loc_clh_PerformanceStockAwardsMember_90558d50-0556-40a9-9091-15643827235c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/COMMITMENTSANDCONTINGENCIESDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#COMMITMENTSANDCONTINGENCIESDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/COMMITMENTSANDCONTINGENCIESDetails" xlink:type="extended" id="i538cbb3dd2ed45ebb5da5346acf04396_COMMITMENTSANDCONTINGENCIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_2bfb0781-c8ba-4db2-a3db-1e274b5fa0d6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LossContingencyAccrualAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_2bfb0781-c8ba-4db2-a3db-1e274b5fa0d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfPermitsIssuedByGovernmentToDumpOrganicLiquid_d23e2526-099f-438e-88a3-04b1f36e20e9" xlink:href="clh-20210630.xsd#clh_NumberOfPermitsIssuedByGovernmentToDumpOrganicLiquid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_NumberOfPermitsIssuedByGovernmentToDumpOrganicLiquid_d23e2526-099f-438e-88a3-04b1f36e20e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfNeighboringMunicipalitiesFilingSeparateLegalProceedings_eb509e09-9935-464c-b2e7-b940d80b02ae" xlink:href="clh-20210630.xsd#clh_NumberOfNeighboringMunicipalitiesFilingSeparateLegalProceedings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_NumberOfNeighboringMunicipalitiesFilingSeparateLegalProceedings_eb509e09-9935-464c-b2e7-b940d80b02ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_LossContingencyGeneralDamagesSoughtValue_96f14643-dee5-4dfe-bf61-f7e3a6ab985a" xlink:href="clh-20210630.xsd#clh_LossContingencyGeneralDamagesSoughtValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_LossContingencyGeneralDamagesSoughtValue_96f14643-dee5-4dfe-bf61-f7e3a6ab985a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_LossContingencyPunitiveDamagesSoughtValue_7d207a05-e56b-4fda-b05c-633cc2d1bc6f" xlink:href="clh-20210630.xsd#clh_LossContingencyPunitiveDamagesSoughtValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_LossContingencyPunitiveDamagesSoughtValue_7d207a05-e56b-4fda-b05c-633cc2d1bc6f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyPendingClaimsNumber_04ff8898-f5b6-4cdc-b745-a1751b430930" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LossContingencyPendingClaimsNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_us-gaap_LossContingencyPendingClaimsNumber_04ff8898-f5b6-4cdc-b745-a1751b430930" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyClaimsSettledAndDismissedNumber_685a71f2-6f7e-4f79-84ea-4a44fae0ea73" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LossContingencyClaimsSettledAndDismissedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_us-gaap_LossContingencyClaimsSettledAndDismissedNumber_685a71f2-6f7e-4f79-84ea-4a44fae0ea73" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyNumberOfSites_ff1e6665-1d02-4e7b-8c0e-00ce3a0ee99a" xlink:href="clh-20210630.xsd#clh_SiteContingencyNumberOfSites"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyNumberOfSites_ff1e6665-1d02-4e7b-8c0e-00ce3a0ee99a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyNumberOfSitesOwnedByEntity_f4b08e2b-722c-4804-b37a-55c368f2b0b2" xlink:href="clh-20210630.xsd#clh_SiteContingencyNumberOfSitesOwnedByEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyNumberOfSitesOwnedByEntity_f4b08e2b-722c-4804-b37a-55c368f2b0b2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyNumberOfSitesOwnedByThirdParty_92bc2218-32e5-4cc7-b969-09e29a3da8ec" xlink:href="clh-20210630.xsd#clh_SiteContingencyNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyNumberOfSitesOwnedByThirdParty_92bc2218-32e5-4cc7-b969-09e29a3da8ec" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyEnvironmentalRemediationExpenseSettledNumberOfSitesOwnedByThirdParty_fa010508-aa45-4e38-8122-3348aa589bca" xlink:href="clh-20210630.xsd#clh_SiteContingencyEnvironmentalRemediationExpenseSettledNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyEnvironmentalRemediationExpenseSettledNumberOfSitesOwnedByThirdParty_fa010508-aa45-4e38-8122-3348aa589bca" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty_f2588f23-e082-457f-aecd-173804712d8e" xlink:href="clh-20210630.xsd#clh_SiteContingencyEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty_f2588f23-e082-457f-aecd-173804712d8e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyNotRequiringEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty_93f49731-ce58-4139-ba46-a783133bf531" xlink:href="clh-20210630.xsd#clh_SiteContingencyNotRequiringEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyNotRequiringEnvironmentalRemediationExpenseNumberOfSitesOwnedByThirdParty_93f49731-ce58-4139-ba46-a783133bf531" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_LossContingencyRangeOfPossibleLossMinimum_92901b7a-344a-4ef7-ac50-40ab9a4f6f04" xlink:href="clh-20210630.xsd#clh_LossContingencyRangeOfPossibleLossMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_LossContingencyRangeOfPossibleLossMinimum_92901b7a-344a-4ef7-ac50-40ab9a4f6f04" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_NumberOfSitesPotentialLiabilityExceedsSubstantialQuota_fcb6953f-27d9-4ddf-a3d5-0d46b023f5f8" xlink:href="clh-20210630.xsd#clh_NumberOfSitesPotentialLiabilityExceedsSubstantialQuota"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_NumberOfSitesPotentialLiabilityExceedsSubstantialQuota_fcb6953f-27d9-4ddf-a3d5-0d46b023f5f8" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPeriodIncreaseDecrease_00af9b6e-389b-45fc-92e4-013ac116c505" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesPeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPeriodIncreaseDecrease_00af9b6e-389b-45fc-92e4-013ac116c505" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyIndemnificationAgreementNumberOfSitesOwnedByThirdParty_0315de7f-98d2-43f3-9efa-5f9a3b0588d3" xlink:href="clh-20210630.xsd#clh_SiteContingencyIndemnificationAgreementNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyIndemnificationAgreementNumberOfSitesOwnedByThirdParty_0315de7f-98d2-43f3-9efa-5f9a3b0588d3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SiteContingencyNoticeReceivedNumberOfSitesOwnedByThirdParty_72133c3c-9ced-4d80-adc2-b5bcdd359fbc" xlink:href="clh-20210630.xsd#clh_SiteContingencyNoticeReceivedNumberOfSitesOwnedByThirdParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_clh_SiteContingencyNoticeReceivedNumberOfSitesOwnedByThirdParty_72133c3c-9ced-4d80-adc2-b5bcdd359fbc" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_b9eaf332-dd79-46f7-bb92-abd1c5de3f09" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_831926a2-ed78-4c01-a05d-3b880cf614b0" xlink:to="loc_us-gaap_LossContingenciesTable_b9eaf332-dd79-46f7-bb92-abd1c5de3f09" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ContingenciesByNatureOfContingencyAxis_e6210231-de3f-4dc9-a05e-508ba8d5ae68" xlink:href="clh-20210630.xsd#clh_ContingenciesByNatureOfContingencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_b9eaf332-dd79-46f7-bb92-abd1c5de3f09" xlink:to="loc_clh_ContingenciesByNatureOfContingencyAxis_e6210231-de3f-4dc9-a05e-508ba8d5ae68" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ContingencyNatureDomain_e6210231-de3f-4dc9-a05e-508ba8d5ae68_default" xlink:href="clh-20210630.xsd#clh_ContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_clh_ContingenciesByNatureOfContingencyAxis_e6210231-de3f-4dc9-a05e-508ba8d5ae68" xlink:to="loc_clh_ContingencyNatureDomain_e6210231-de3f-4dc9-a05e-508ba8d5ae68_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:href="clh-20210630.xsd#clh_ContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_clh_ContingenciesByNatureOfContingencyAxis_e6210231-de3f-4dc9-a05e-508ba8d5ae68" xlink:to="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_LegalAndAdministrativeProceedingsMember_37af97ef-485f-4152-9162-39c4673707a5" xlink:href="clh-20210630.xsd#clh_LegalAndAdministrativeProceedingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_LegalAndAdministrativeProceedingsMember_37af97ef-485f-4152-9162-39c4673707a5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_VilleMercierMember_911176b6-a070-4b8a-b093-dab31613a7f0" xlink:href="clh-20210630.xsd#clh_VilleMercierMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_VilleMercierMember_911176b6-a070-4b8a-b093-dab31613a7f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SuperfundProceedingsMember_2f1889be-cd68-43e2-a48c-2bda1bf344aa" xlink:href="clh-20210630.xsd#clh_SuperfundProceedingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_SuperfundProceedingsMember_2f1889be-cd68-43e2-a48c-2bda1bf344aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_BRFacilityMember_5729d4bc-1a86-44ad-8e8c-38d576684aeb" xlink:href="clh-20210630.xsd#clh_BRFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_BRFacilityMember_5729d4bc-1a86-44ad-8e8c-38d576684aeb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_CertainOtherThirdPartySitesMember_d7ccbf37-c0e6-43ec-98f4-da993ee543fd" xlink:href="clh-20210630.xsd#clh_CertainOtherThirdPartySitesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_CertainOtherThirdPartySitesMember_d7ccbf37-c0e6-43ec-98f4-da993ee543fd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_KleenPerformanceProductsMember_b42566a7-d093-4bfa-9b80-2ec10576a85d" xlink:href="clh-20210630.xsd#clh_KleenPerformanceProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_KleenPerformanceProductsMember_b42566a7-d093-4bfa-9b80-2ec10576a85d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_FederalAndStateEnforcementActionsMember_14d30196-edcb-476b-8be7-a237591b1e30" xlink:href="clh-20210630.xsd#clh_FederalAndStateEnforcementActionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ContingencyNatureDomain_61b0a16d-ff8b-4af3-a684-257ee8139c7c" xlink:to="loc_clh_FederalAndStateEnforcementActionsMember_14d30196-edcb-476b-8be7-a237591b1e30" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteAxis_382ed4f9-b961-48b2-8e1d-9c25f0e5b273" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_b9eaf332-dd79-46f7-bb92-abd1c5de3f09" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteAxis_382ed4f9-b961-48b2-8e1d-9c25f0e5b273" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_382ed4f9-b961-48b2-8e1d-9c25f0e5b273_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_382ed4f9-b961-48b2-8e1d-9c25f0e5b273" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_382ed4f9-b961-48b2-8e1d-9c25f0e5b273_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_00a2f1c6-0015-4475-bc99-611235533a30" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_382ed4f9-b961-48b2-8e1d-9c25f0e5b273" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_00a2f1c6-0015-4475-bc99-611235533a30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_RemedialLiabilitiesForInactiveSitesMember_927c2db0-6efd-4064-92c4-903d1a1ba0cc" xlink:href="clh-20210630.xsd#clh_RemedialLiabilitiesForInactiveSitesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_00a2f1c6-0015-4475-bc99-611235533a30" xlink:to="loc_clh_RemedialLiabilitiesForInactiveSitesMember_927c2db0-6efd-4064-92c4-903d1a1ba0cc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/SEGMENTREPORTINGReconciliationofThirdPartyRevenuestoDirectRevenuesDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#SEGMENTREPORTINGReconciliationofThirdPartyRevenuestoDirectRevenuesDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/SEGMENTREPORTINGReconciliationofThirdPartyRevenuestoDirectRevenuesDetails" xlink:type="extended" id="ic8db604e46c04dfc8e3826fefcf260ca_SEGMENTREPORTINGReconciliationofThirdPartyRevenuestoDirectRevenuesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_a13f5a94-0c34-44ac-875a-424c4fb7120c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_141f54a5-66b5-48a8-9a38-aafddadf528d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a13f5a94-0c34-44ac-875a-424c4fb7120c" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_141f54a5-66b5-48a8-9a38-aafddadf528d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a13f5a94-0c34-44ac-875a-424c4fb7120c" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_aa469ea8-8831-4b61-ba38-32789e6f3641" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:to="loc_srt_ConsolidationItemsAxis_aa469ea8-8831-4b61-ba38-32789e6f3641" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_aa469ea8-8831-4b61-ba38-32789e6f3641_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_aa469ea8-8831-4b61-ba38-32789e6f3641" xlink:to="loc_srt_ConsolidationItemsDomain_aa469ea8-8831-4b61-ba38-32789e6f3641_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_aa469ea8-8831-4b61-ba38-32789e6f3641" xlink:to="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_d6d32ba6-f557-4494-884b-656d56253aa9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:to="loc_us-gaap_OperatingSegmentsMember_d6d32ba6-f557-4494-884b-656d56253aa9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_b5146ce4-6482-41c2-af5d-86667ae639eb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:to="loc_us-gaap_IntersegmentEliminationMember_b5146ce4-6482-41c2-af5d-86667ae639eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_126d3e95-bc77-447a-b9e6-2549f035917a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:to="loc_us-gaap_CorporateNonSegmentMember_126d3e95-bc77-447a-b9e6-2549f035917a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_OperatingSegmentsAndCorporateNonSegmentMember_fd4a5a6e-6731-47ff-982d-363894997ad6" xlink:href="clh-20210630.xsd#clh_OperatingSegmentsAndCorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_9ee35170-a182-4c88-9083-ad8459fe32a4" xlink:to="loc_clh_OperatingSegmentsAndCorporateNonSegmentMember_fd4a5a6e-6731-47ff-982d-363894997ad6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_d38001f8-1665-4b8f-a65a-7db09eea9c3c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_d38001f8-1665-4b8f-a65a-7db09eea9c3c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_d38001f8-1665-4b8f-a65a-7db09eea9c3c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_d38001f8-1665-4b8f-a65a-7db09eea9c3c" xlink:to="loc_us-gaap_SegmentDomain_d38001f8-1665-4b8f-a65a-7db09eea9c3c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_443c8320-6f3d-4a7e-a3ac-eeca600e1752" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_d38001f8-1665-4b8f-a65a-7db09eea9c3c" xlink:to="loc_us-gaap_SegmentDomain_443c8320-6f3d-4a7e-a3ac-eeca600e1752" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_04678e17-2deb-4cd4-9b06-daf905c75ef8" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_443c8320-6f3d-4a7e-a3ac-eeca600e1752" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_04678e17-2deb-4cd4-9b06-daf905c75ef8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_960c18b7-08df-48d8-80d7-833c30eb4851" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_443c8320-6f3d-4a7e-a3ac-eeca600e1752" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_960c18b7-08df-48d8-80d7-833c30eb4851" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsAxis_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:to="loc_us-gaap_SubsegmentsAxis_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsDomain_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsAxis_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25" xlink:to="loc_us-gaap_SubsegmentsDomain_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsDomain_0e305517-69e6-4c07-a84a-f3ccc067475d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsAxis_bd0d9475-ac66-42e0-a6c0-4eaf4a4a9e25" xlink:to="loc_us-gaap_SubsegmentsDomain_0e305517-69e6-4c07-a84a-f3ccc067475d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsConsolidationItemsAxis_3c5adfef-59aa-41b3-aa0f-53d6319f1c74" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_64ba368f-a7a1-45fe-b9d7-a01a4f071987" xlink:to="loc_us-gaap_SubsegmentsConsolidationItemsAxis_3c5adfef-59aa-41b3-aa0f-53d6319f1c74" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsConsolidationItemsDomain_3c5adfef-59aa-41b3-aa0f-53d6319f1c74_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsConsolidationItemsAxis_3c5adfef-59aa-41b3-aa0f-53d6319f1c74" xlink:to="loc_us-gaap_SubsegmentsConsolidationItemsDomain_3c5adfef-59aa-41b3-aa0f-53d6319f1c74_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsConsolidationItemsDomain_d2ece4e6-0391-4105-b301-524c8a0656b4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsConsolidationItemsAxis_3c5adfef-59aa-41b3-aa0f-53d6319f1c74" xlink:to="loc_us-gaap_SubsegmentsConsolidationItemsDomain_d2ece4e6-0391-4105-b301-524c8a0656b4" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/SEGMENTREPORTINGReconciliationtoConsolidatedStatementsofIncometoAdjustedEBITDADetails" xlink:type="simple" xlink:href="clh-20210630.xsd#SEGMENTREPORTINGReconciliationtoConsolidatedStatementsofIncometoAdjustedEBITDADetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/SEGMENTREPORTINGReconciliationtoConsolidatedStatementsofIncometoAdjustedEBITDADetails" xlink:type="extended" id="i6e1d3962f6b04eab91c5e3cc3b748a93_SEGMENTREPORTINGReconciliationtoConsolidatedStatementsofIncometoAdjustedEBITDADetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_0ed90ff7-fbdb-4d5c-8444-c0c80f623fcd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_IncomeLossFromContinuingOperationsBeforeInterestTaxDepreciationAndAmortizationNet_e74b1c3e-fa44-4b10-88db-27537bfed990" xlink:href="clh-20210630.xsd#clh_IncomeLossFromContinuingOperationsBeforeInterestTaxDepreciationAndAmortizationNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0ed90ff7-fbdb-4d5c-8444-c0c80f623fcd" xlink:to="loc_clh_IncomeLossFromContinuingOperationsBeforeInterestTaxDepreciationAndAmortizationNet_e74b1c3e-fa44-4b10-88db-27537bfed990" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:href="clh-20210630.xsd#clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0ed90ff7-fbdb-4d5c-8444-c0c80f623fcd" xlink:to="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_AccretionOfEnvironmentalLiabilities_40820ccb-8698-4b58-bd3d-a41b99f0432e" xlink:href="clh-20210630.xsd#clh_AccretionOfEnvironmentalLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_clh_AccretionOfEnvironmentalLiabilities_40820ccb-8698-4b58-bd3d-a41b99f0432e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_eb42f8dd-f8da-488d-95bc-a21646c15cd3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_ShareBasedCompensation_eb42f8dd-f8da-488d-95bc-a21646c15cd3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_011c72d3-fca6-4b98-82b1-33481284e1a8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_011c72d3-fca6-4b98-82b1-33481284e1a8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_85756c35-eeb9-473c-846a-4c0ed6d5f6dc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_OperatingIncomeLoss_85756c35-eeb9-473c-846a-4c0ed6d5f6dc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_11ee27e0-5d3b-495a-812b-446365b25483" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_11ee27e0-5d3b-495a-812b-446365b25483" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_4d5de54f-08a7-4eda-a3e0-9309902e19a8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_4d5de54f-08a7-4eda-a3e0-9309902e19a8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_6b6f3011-25a3-423e-a364-b9c76665c0aa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_clh_ReconciliationOfNetIncomeToAdjustedEBITDAAbstract_8aca213a-b1d8-4e60-8536-69fadd1fcc0a" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_6b6f3011-25a3-423e-a364-b9c76665c0aa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_a3ebaac3-0ef7-4346-aac6-d057f56f5a9d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0ed90ff7-fbdb-4d5c-8444-c0c80f623fcd" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_a3ebaac3-0ef7-4346-aac6-d057f56f5a9d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_0671ce6e-30be-4092-af86-efc00e8602fc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0ed90ff7-fbdb-4d5c-8444-c0c80f623fcd" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_0671ce6e-30be-4092-af86-efc00e8602fc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_d0ce2620-3c4d-4e65-a4f9-52d092ffc941" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_0671ce6e-30be-4092-af86-efc00e8602fc" xlink:to="loc_srt_ConsolidationItemsAxis_d0ce2620-3c4d-4e65-a4f9-52d092ffc941" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_d0ce2620-3c4d-4e65-a4f9-52d092ffc941_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_d0ce2620-3c4d-4e65-a4f9-52d092ffc941" xlink:to="loc_srt_ConsolidationItemsDomain_d0ce2620-3c4d-4e65-a4f9-52d092ffc941_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_d0ce2620-3c4d-4e65-a4f9-52d092ffc941" xlink:to="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_ec494bb0-429f-414b-a3f8-c30eaaf90a46" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:to="loc_us-gaap_OperatingSegmentsMember_ec494bb0-429f-414b-a3f8-c30eaaf90a46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_45a91c38-489b-4c0f-bb14-747ed5205450" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:to="loc_us-gaap_IntersegmentEliminationMember_45a91c38-489b-4c0f-bb14-747ed5205450" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_7951d14e-3edb-4e36-90fc-e263d188e1e1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:to="loc_us-gaap_CorporateNonSegmentMember_7951d14e-3edb-4e36-90fc-e263d188e1e1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_OperatingSegmentsAndCorporateNonSegmentMember_f70d1136-f285-4be2-a137-e3b75386aa48" xlink:href="clh-20210630.xsd#clh_OperatingSegmentsAndCorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_94e3245f-8729-47d8-b5ec-4da30740382c" xlink:to="loc_clh_OperatingSegmentsAndCorporateNonSegmentMember_f70d1136-f285-4be2-a137-e3b75386aa48" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_fc9491a2-f963-4438-9302-561bb8cdde5c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_0671ce6e-30be-4092-af86-efc00e8602fc" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_fc9491a2-f963-4438-9302-561bb8cdde5c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_fc9491a2-f963-4438-9302-561bb8cdde5c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_fc9491a2-f963-4438-9302-561bb8cdde5c" xlink:to="loc_us-gaap_SegmentDomain_fc9491a2-f963-4438-9302-561bb8cdde5c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_f8120b48-f0aa-47f7-bbb8-a82f7150eb08" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_fc9491a2-f963-4438-9302-561bb8cdde5c" xlink:to="loc_us-gaap_SegmentDomain_f8120b48-f0aa-47f7-bbb8-a82f7150eb08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_ea07acb8-8a4e-4853-9a7d-e995ae860bd7" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_f8120b48-f0aa-47f7-bbb8-a82f7150eb08" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_ea07acb8-8a4e-4853-9a7d-e995ae860bd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_486b41fd-cb74-4833-b725-6c9775e72c23" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_f8120b48-f0aa-47f7-bbb8-a82f7150eb08" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_486b41fd-cb74-4833-b725-6c9775e72c23" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/SEGMENTREPORTINGScheduleofCertainAssetsbyReportableSegmentDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#SEGMENTREPORTINGScheduleofCertainAssetsbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/SEGMENTREPORTINGScheduleofCertainAssetsbyReportableSegmentDetails" xlink:type="extended" id="ic638ff081ea240f58b209168df4e68aa_SEGMENTREPORTINGScheduleofCertainAssetsbyReportableSegmentDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_dbef7247-caf4-437a-aa0a-fd69194b826a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_dbef7247-caf4-437a-aa0a-fd69194b826a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_35f0164c-8cc6-46e4-9ff7-366e2801ddce" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:to="loc_us-gaap_Goodwill_35f0164c-8cc6-46e4-9ff7-366e2801ddce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_862938f9-4d41-4d0a-89d5-3c778eb8dae2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_862938f9-4d41-4d0a-89d5-3c778eb8dae2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_76f63c05-76e0-4778-a026-e6f6efa04264" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:to="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_76f63c05-76e0-4778-a026-e6f6efa04264" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_29a7e778-4c76-4150-94e0-df375e363613" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_82daf254-d692-44a9-86a8-35e0cab6b861" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_29a7e778-4c76-4150-94e0-df375e363613" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_4d89981f-2818-4cfb-97f0-e4d726f76b77" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_29a7e778-4c76-4150-94e0-df375e363613" xlink:to="loc_srt_ConsolidationItemsAxis_4d89981f-2818-4cfb-97f0-e4d726f76b77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_4d89981f-2818-4cfb-97f0-e4d726f76b77_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_4d89981f-2818-4cfb-97f0-e4d726f76b77" xlink:to="loc_srt_ConsolidationItemsDomain_4d89981f-2818-4cfb-97f0-e4d726f76b77_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_4c226076-b42b-4210-a3c0-9d259e0e7daa" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_4d89981f-2818-4cfb-97f0-e4d726f76b77" xlink:to="loc_srt_ConsolidationItemsDomain_4c226076-b42b-4210-a3c0-9d259e0e7daa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_5063a302-f6f2-40f8-bfe4-eb925b19b848" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_4c226076-b42b-4210-a3c0-9d259e0e7daa" xlink:to="loc_us-gaap_OperatingSegmentsMember_5063a302-f6f2-40f8-bfe4-eb925b19b848" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_7e81ecbc-0641-4db2-9e3e-cc656dbec1ed" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_4c226076-b42b-4210-a3c0-9d259e0e7daa" xlink:to="loc_us-gaap_CorporateNonSegmentMember_7e81ecbc-0641-4db2-9e3e-cc656dbec1ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_81228950-2909-4147-af07-75e3cac0e979" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_29a7e778-4c76-4150-94e0-df375e363613" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_81228950-2909-4147-af07-75e3cac0e979" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_81228950-2909-4147-af07-75e3cac0e979_default" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_81228950-2909-4147-af07-75e3cac0e979" xlink:to="loc_us-gaap_SegmentDomain_81228950-2909-4147-af07-75e3cac0e979_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_71fa83a6-d870-4bcb-aad6-3aef7e2eb382" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_81228950-2909-4147-af07-75e3cac0e979" xlink:to="loc_us-gaap_SegmentDomain_71fa83a6-d870-4bcb-aad6-3aef7e2eb382" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_EnvironmentalServicesSegmentMember_83401106-1f67-4987-9008-15052d657e3a" xlink:href="clh-20210630.xsd#clh_EnvironmentalServicesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_71fa83a6-d870-4bcb-aad6-3aef7e2eb382" xlink:to="loc_clh_EnvironmentalServicesSegmentMember_83401106-1f67-4987-9008-15052d657e3a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_a2aaec65-8549-4241-91b6-bb2ccd240d28" xlink:href="clh-20210630.xsd#clh_SafetyKleenSustainabilitySolutionsSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_71fa83a6-d870-4bcb-aad6-3aef7e2eb382" xlink:to="loc_clh_SafetyKleenSustainabilitySolutionsSegmentMember_a2aaec65-8549-4241-91b6-bb2ccd240d28" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cleanharbors.com/role/SEGMENTREPORTINGLonglivedAssetsbyGeographicAreasDetails" xlink:type="simple" xlink:href="clh-20210630.xsd#SEGMENTREPORTINGLonglivedAssetsbyGeographicAreasDetails"/>
  <link:definitionLink xlink:role="http://www.cleanharbors.com/role/SEGMENTREPORTINGLonglivedAssetsbyGeographicAreasDetails" xlink:type="extended" id="i6c8f78bead6049d7ba96a05da59349c1_SEGMENTREPORTINGLonglivedAssetsbyGeographicAreasDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f81fee67-dba5-4f0d-9096-44f81caccb3f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_8a75f67e-f0a1-4fd6-9153-3840415f7d30" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f81fee67-dba5-4f0d-9096-44f81caccb3f" xlink:to="loc_us-gaap_Assets_8a75f67e-f0a1-4fd6-9153-3840415f7d30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_134f0f9d-232d-4a4e-a2b1-43c00a54b912" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f81fee67-dba5-4f0d-9096-44f81caccb3f" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_134f0f9d-232d-4a4e-a2b1-43c00a54b912" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_5c468d88-13b1-4277-af9f-19641a15c41c" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_134f0f9d-232d-4a4e-a2b1-43c00a54b912" xlink:to="loc_srt_StatementGeographicalAxis_5c468d88-13b1-4277-af9f-19641a15c41c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_5c468d88-13b1-4277-af9f-19641a15c41c_default" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_5c468d88-13b1-4277-af9f-19641a15c41c" xlink:to="loc_srt_SegmentGeographicalDomain_5c468d88-13b1-4277-af9f-19641a15c41c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_a02e0764-7e46-4d8b-a4e0-77f1e5d047f5" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_5c468d88-13b1-4277-af9f-19641a15c41c" xlink:to="loc_srt_SegmentGeographicalDomain_a02e0764-7e46-4d8b-a4e0-77f1e5d047f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_e56ce799-6827-47fb-8f58-18a9903bfdc4" xlink:href="https://xbrl.sec.gov/country/2021/country-2021.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a02e0764-7e46-4d8b-a4e0-77f1e5d047f5" xlink:to="loc_country_US_e56ce799-6827-47fb-8f58-18a9903bfdc4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonUsMember_fd60ec57-d9c0-4eb0-97da-f06d2b55e807" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NonUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a02e0764-7e46-4d8b-a4e0-77f1e5d047f5" xlink:to="loc_us-gaap_NonUsMember_fd60ec57-d9c0-4eb0-97da-f06d2b55e807" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
