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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:01a0aaff-8eff-75da-8220-83629a068078,g:97193030-2f36-44cb-ab4c-b18f22fd5df0-->
<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.wm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITY" xlink:type="simple" xlink:href="wm-20260930.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITY"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_01a0aaff-906c-76c6-9e34-a185974a2672" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_01a0aaff-906c-7796-a602-c3411a74bbb9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_01a0aaff-906c-76c6-9e34-a185974a2672" xlink:to="loc_us-gaap_StatementTable_01a0aaff-906c-7796-a602-c3411a74bbb9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-906c-7303-97fa-72e9aea92675" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_01a0aaff-906c-7796-a602-c3411a74bbb9" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-906c-7303-97fa-72e9aea92675" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-7303-97fa-72e9aea92675_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-906c-7303-97fa-72e9aea92675" xlink:to="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-7303-97fa-72e9aea92675_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-906c-7303-97fa-72e9aea92675" xlink:to="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_01a0aaff-906c-71b6-adfb-6402822ab9c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_CommonStockMember_01a0aaff-906c-71b6-adfb-6402822ab9c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_01a0aaff-906c-7936-bd89-901a141c0c5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_01a0aaff-906c-7936-bd89-901a141c0c5f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_01a0aaff-906c-7265-a5af-f33022a2e93a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_RetainedEarningsMember_01a0aaff-906c-7265-a5af-f33022a2e93a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a0aaff-906c-76c5-b7fd-f1a141424bf9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a0aaff-906c-76c5-b7fd-f1a141424bf9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_01a0aaff-906c-7f0b-92b0-6de53effb64a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_TreasuryStockCommonMember_01a0aaff-906c-7f0b-92b0-6de53effb64a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_01a0aaff-906c-76bf-aa68-2fcf7ed69745" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-906c-70ef-bdbf-f36583134c6b" xlink:to="loc_us-gaap_NoncontrollingInterestMember_01a0aaff-906c-76bf-aa68-2fcf7ed69745" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a0aaff-906c-76c6-9e34-a185974a2672" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-906c-725e-9415-f438ed6c6ba7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-906c-725e-9415-f438ed6c6ba7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_01a0aaff-906c-77e6-bfc3-2cc4d69612c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_01a0aaff-906c-77e6-bfc3-2cc4d69612c8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_01a0aaff-906c-7f62-ac60-bc50b519e4e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_TreasuryStockCommonShares_01a0aaff-906c-7f62-ac60-bc50b519e4e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_01a0aaff-906c-7a85-889c-434c9cf944cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_ProfitLoss_01a0aaff-906c-7a85-889c-434c9cf944cf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_01a0aaff-906c-74bd-b012-30a82318642a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_01a0aaff-906c-74bd-b012-30a82318642a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_01a0aaff-906c-7932-8b19-e48f3507fa46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_DividendsCommonStockCash_01a0aaff-906c-7932-8b19-e48f3507fa46" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockValueSharesIssuedNetOfTaxWithholdings_01a0aaff-906c-7448-9627-3bddabe78cb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockValueSharesIssuedNetOfTaxWithholdings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_RestrictedStockValueSharesIssuedNetOfTaxWithholdings_01a0aaff-906c-7448-9627-3bddabe78cb5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockSharesIssuedNetOfSharesForTaxWithholdings_01a0aaff-906c-74cf-a5d0-ead6f2145244" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockSharesIssuedNetOfSharesForTaxWithholdings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_RestrictedStockSharesIssuedNetOfSharesForTaxWithholdings_01a0aaff-906c-74cf-a5d0-ead6f2145244" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a0aaff-906c-7bac-a731-aeb130168091" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a0aaff-906c-7bac-a731-aeb130168091" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_01a0aaff-906c-7d28-ae3c-ffcff3628937" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_01a0aaff-906c-7d28-ae3c-ffcff3628937" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_01a0aaff-906c-7a9a-a638-0a2627209321" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_01a0aaff-906c-7a9a-a638-0a2627209321" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_01a0aaff-906c-753d-b7ea-db6823621674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_01a0aaff-906c-753d-b7ea-db6823621674" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther_01a0aaff-906c-7af1-9b86-03ddab1aed49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_StockholdersEquityOther_01a0aaff-906c-7af1-9b86-03ddab1aed49" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOtherShares_01a0aaff-906c-7684-bea6-e87a88f27a0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityOtherShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a0aaff-906c-7f2c-ad61-1c8ccabe0f3e" xlink:to="loc_us-gaap_StockholdersEquityOtherShares_01a0aaff-906c-7684-bea6-e87a88f27a0a" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-906c-7c97-bc14-3e9c0fe82cfb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_01a0aaff-906c-749c-b3ab-929e28eb38b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_01a0aaff-906c-721e-a772-9664ddd5da54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonShares"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/BasisofPresentationDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#BasisofPresentationDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/BasisofPresentationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostTable_01a0aaff-906c-7b3d-bd94-a2bec859bd29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_us-gaap_CapitalizedContractCostTable_01a0aaff-906c-7b3d-bd94-a2bec859bd29" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a0aaff-906c-7cca-8418-5075fbe05967" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_01a0aaff-906c-7b3d-bd94-a2bec859bd29" xlink:to="loc_srt_RangeAxis_01a0aaff-906c-7cca-8418-5075fbe05967" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-7cca-8418-5075fbe05967_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-7cca-8418-5075fbe05967" xlink:to="loc_srt_RangeMember_01a0aaff-906c-7cca-8418-5075fbe05967_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-799c-b98b-23b7cacf828a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-7cca-8418-5075fbe05967" xlink:to="loc_srt_RangeMember_01a0aaff-906c-799c-b98b-23b7cacf828a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a0aaff-906c-784c-b33d-db2137c0943a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-799c-b98b-23b7cacf828a" xlink:to="loc_srt_MinimumMember_01a0aaff-906c-784c-b33d-db2137c0943a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a0aaff-906c-72f0-8517-f7dccaec45ba" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-799c-b98b-23b7cacf828a" xlink:to="loc_srt_MaximumMember_01a0aaff-906c-72f0-8517-f7dccaec45ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_01a0aaff-906c-7639-b244-445c79cc3868" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_us-gaap_NumberOfReportableSegments_01a0aaff-906c-7639-b244-445c79cc3868" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_DeferredRevenueRecognitionPeriod_01a0aaff-906c-7dc2-b566-a815c7829ebc" xlink:href="wm-20260930.xsd#wm_DeferredRevenueRecognitionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_wm_DeferredRevenueRecognitionPeriod_01a0aaff-906c-7dc2-b566-a815c7829ebc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_01a0aaff-906c-783d-91ff-6ee24ab89177" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostAmortizationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_01a0aaff-906c-783d-91ff-6ee24ab89177" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostNet_01a0aaff-906c-7817-808e-f6f5da806f24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_us-gaap_CapitalizedContractCostNet_01a0aaff-906c-7817-808e-f6f5da806f24" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredSalesInducementsNet_01a0aaff-906c-743a-8ccc-3b5968fedb3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredSalesInducementsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_01a0aaff-906c-7025-93c9-e569d9c25e02" xlink:to="loc_us-gaap_DeferredSalesInducementsNet_01a0aaff-906c-743a-8ccc-3b5968fedb3c" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/LandfillandEnvironmentalRemediationLiabilitiesLiabilitiesforLandfillandEnvironmentalRemediationCostsDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#LandfillandEnvironmentalRemediationLiabilitiesLiabilitiesforLandfillandEnvironmentalRemediationCostsDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/LandfillandEnvironmentalRemediationLiabilitiesLiabilitiesforLandfillandEnvironmentalRemediationCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEnvironmentalExitCostTable_01a0aaff-906c-7bb7-9558-e2b3e25ce16a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEnvironmentalExitCostTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_us-gaap_ScheduleOfEnvironmentalExitCostTable_01a0aaff-906c-7bb7-9558-e2b3e25ce16a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_01a0aaff-906c-70a9-97a4-3f3d226ac679" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEnvironmentalExitCostTable_01a0aaff-906c-7bb7-9558-e2b3e25ce16a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_01a0aaff-906c-70a9-97a4-3f3d226ac679" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_01a0aaff-906c-70a9-97a4-3f3d226ac679_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_01a0aaff-906c-70a9-97a4-3f3d226ac679" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_01a0aaff-906c-70a9-97a4-3f3d226ac679_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_01a0aaff-906c-71ee-849e-5fbab9210ba3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_01a0aaff-906c-70a9-97a4-3f3d226ac679" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_01a0aaff-906c-71ee-849e-5fbab9210ba3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandfillMember_01a0aaff-906c-7fb7-9bea-444199aa7d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LandfillMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_01a0aaff-906c-71ee-849e-5fbab9210ba3" xlink:to="loc_us-gaap_LandfillMember_01a0aaff-906c-7fb7-9bea-444199aa7d1e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostByPropertyAxis_01a0aaff-906c-799d-a5d1-19beeca6e883" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostByPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEnvironmentalExitCostTable_01a0aaff-906c-7bb7-9558-e2b3e25ce16a" xlink:to="loc_us-gaap_EnvironmentalExitCostByPropertyAxis_01a0aaff-906c-799d-a5d1-19beeca6e883" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostsNameOfPropertyDomain_01a0aaff-906c-799d-a5d1-19beeca6e883_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostsNameOfPropertyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EnvironmentalExitCostByPropertyAxis_01a0aaff-906c-799d-a5d1-19beeca6e883" xlink:to="loc_us-gaap_EnvironmentalExitCostsNameOfPropertyDomain_01a0aaff-906c-799d-a5d1-19beeca6e883_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostsNameOfPropertyDomain_01a0aaff-906c-77c5-8e39-8c25c891fe38" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostsNameOfPropertyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EnvironmentalExitCostByPropertyAxis_01a0aaff-906c-799d-a5d1-19beeca6e883" xlink:to="loc_us-gaap_EnvironmentalExitCostsNameOfPropertyDomain_01a0aaff-906c-77c5-8e39-8c25c891fe38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_EnvironmentalCostsMember_01a0aaff-906c-7c06-ad08-55b4a4682e17" xlink:href="wm-20260930.xsd#wm_EnvironmentalCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostsNameOfPropertyDomain_01a0aaff-906c-77c5-8e39-8c25c891fe38" xlink:to="loc_wm_EnvironmentalCostsMember_01a0aaff-906c-7c06-ad08-55b4a4682e17" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationAbstract_01a0afb5-bc1b-71fd-bba7-ffe5caf8ba7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_us-gaap_AssetRetirementObligationAbstract_01a0afb5-bc1b-71fd-bba7-ffe5caf8ba7f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationCurrent_01a0aaff-906c-7add-b528-7f3180b0e00e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligationCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationAbstract_01a0afb5-bc1b-71fd-bba7-ffe5caf8ba7f" xlink:to="loc_us-gaap_AssetRetirementObligationCurrent_01a0aaff-906c-7add-b528-7f3180b0e00e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationsNoncurrent_01a0aaff-906c-79b4-a179-b88617212c1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligationsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationAbstract_01a0afb5-bc1b-71fd-bba7-ffe5caf8ba7f" xlink:to="loc_us-gaap_AssetRetirementObligationsNoncurrent_01a0aaff-906c-79b4-a179-b88617212c1d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligation_01a0aaff-906c-7a12-8c1f-0ea9c65a21d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetRetirementObligationAbstract_01a0afb5-bc1b-71fd-bba7-ffe5caf8ba7f" xlink:to="loc_us-gaap_AssetRetirementObligation_01a0aaff-906c-7a12-8c1f-0ea9c65a21d1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesAbstract_01a0afb6-79ec-7c37-a503-7e4049501d15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingenciesAbstract_01a0afb6-79ec-7c37-a503-7e4049501d15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_01a0aaff-906c-78d4-bf8a-dcb1794b11a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedEnvironmentalLossContingenciesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesAbstract_01a0afb6-79ec-7c37-a503-7e4049501d15" xlink:to="loc_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_01a0aaff-906c-78d4-bf8a-dcb1794b11a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_01a0aaff-906c-7ff6-b33b-66c68e381aa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesAbstract_01a0afb6-79ec-7c37-a503-7e4049501d15" xlink:to="loc_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_01a0aaff-906c-7ff6-b33b-66c68e381aa3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-72ca-983d-37bfe2f8097f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccrualForEnvironmentalLossContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesAbstract_01a0afb6-79ec-7c37-a503-7e4049501d15" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-72ca-983d-37bfe2f8097f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCosts_01a0aaff-906c-7742-9b8f-543de9770de3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCosts_01a0aaff-906c-7742-9b8f-543de9770de3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCostsNoncurrent_01a0aaff-906c-78bc-9ff7-7bbf9815b2dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCostsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_us-gaap_AccruedCappingClosurePostClosureAndEnvironmentalCostsNoncurrent_01a0aaff-906c-78bc-9ff7-7bbf9815b2dd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_AccruedCappingAndEnvironmentalCosts_01a0aaff-906c-766e-9da9-b0244c240923" xlink:href="wm-20260930.xsd#wm_AccruedCappingAndEnvironmentalCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalExitCostLineItems_01a0aaff-906c-786c-8ca9-204648bb8061" xlink:to="loc_wm_AccruedCappingAndEnvironmentalCosts_01a0aaff-906c-766e-9da9-b0244c240923" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/DebtandDerivativesScheduleofDebtDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#DebtandDerivativesScheduleofDebtDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/DebtandDerivativesScheduleofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-7e29-a02a-c860001e1f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-7e29-a02a-c860001e1f2b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-79b4-b40a-64bdaa1187c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-7e29-a02a-c860001e1f2b" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-79b4-b40a-64bdaa1187c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-79b4-b40a-64bdaa1187c7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-79b4-b40a-64bdaa1187c7" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-79b4-b40a-64bdaa1187c7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-79b4-b40a-64bdaa1187c7" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a11cbd-e90a-70d6-93a5-1c04f8c31e62" xlink:href="wm-20260930.xsd#wm_A3.5BillionRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:to="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a11cbd-e90a-70d6-93a5-1c04f8c31e62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_SeniorNotesDue2054Member_01a0aaff-906c-7596-9813-4af89a280f78" xlink:href="wm-20260930.xsd#wm_SeniorNotesDue2054Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:to="loc_wm_SeniorNotesDue2054Member_01a0aaff-906c-7596-9813-4af89a280f78" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CanadianSeniorNotesDue2026Member_01a0aaff-906c-7755-b99f-29c5b502a332" xlink:href="wm-20260930.xsd#wm_CanadianSeniorNotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:to="loc_wm_CanadianSeniorNotesDue2026Member_01a0aaff-906c-7755-b99f-29c5b502a332" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CanadianSeniorNotesDue2033Member_01a0aaff-906c-7ce7-a64f-604b7ce80821" xlink:href="wm-20260930.xsd#wm_CanadianSeniorNotesDue2033Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:to="loc_wm_CanadianSeniorNotesDue2033Member_01a0aaff-906c-7ce7-a64f-604b7ce80821" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_TaxExemptBondsDue2055Member_01a0aaff-906c-7b9a-9e56-721f4ecf1cad" xlink:href="wm-20260930.xsd#wm_TaxExemptBondsDue2055Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7776-9284-254e995a7606" xlink:to="loc_wm_TaxExemptBondsDue2055Member_01a0aaff-906c-7b9a-9e56-721f4ecf1cad" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a0aaff-906c-75ca-88bb-9c0fd7aef6da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-7e29-a02a-c860001e1f2b" xlink:to="loc_srt_RangeAxis_01a0aaff-906c-75ca-88bb-9c0fd7aef6da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-75ca-88bb-9c0fd7aef6da_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-75ca-88bb-9c0fd7aef6da" xlink:to="loc_srt_RangeMember_01a0aaff-906c-75ca-88bb-9c0fd7aef6da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-7344-8988-9e62c585754e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-75ca-88bb-9c0fd7aef6da" xlink:to="loc_srt_RangeMember_01a0aaff-906c-7344-8988-9e62c585754e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a0aaff-906c-7d43-ab31-cea7f5750366" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-7344-8988-9e62c585754e" xlink:to="loc_srt_MinimumMember_01a0aaff-906c-7d43-ab31-cea7f5750366" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a0aaff-906c-7d59-9d73-07f180a84f46" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-7344-8988-9e62c585754e" xlink:to="loc_srt_MaximumMember_01a0aaff-906c-7d59-9d73-07f180a84f46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a0affe-6329-7389-9a2b-d0925fe3b44e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-7e29-a02a-c860001e1f2b" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a0affe-6329-7389-9a2b-d0925fe3b44e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7389-9a2b-d0925fe3b44e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0affe-6329-7389-9a2b-d0925fe3b44e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7389-9a2b-d0925fe3b44e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7af1-8c59-c5eb4e569a84" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0affe-6329-7389-9a2b-d0925fe3b44e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7af1-8c59-c5eb4e569a84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_01a0b023-711c-742e-af62-0b7bab3ede1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7af1-8c59-c5eb4e569a84" xlink:to="loc_us-gaap_CommercialPaperMember_01a0b023-711c-742e-af62-0b7bab3ede1b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_01a0affe-94c0-722d-8a98-88d89d572a52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7af1-8c59-c5eb4e569a84" xlink:to="loc_us-gaap_SeniorNotesMember_01a0affe-94c0-722d-8a98-88d89d572a52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BondsMember_01a0afff-e976-7711-a575-488a8f8992e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0affe-6329-7af1-8c59-c5eb4e569a84" xlink:to="loc_us-gaap_BondsMember_01a0afff-e976-7711-a575-488a8f8992e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_01a0aaff-906c-7964-9918-79dd3cd789cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_01a0aaff-906c-7964-9918-79dd3cd789cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0aaff-906c-7c2a-a82d-09a9cd406d96" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0aaff-906c-7c2a-a82d-09a9cd406d96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_01a0aff3-0339-7024-a0f2-2ef4eaa6b333" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_01a0aff3-0339-7024-a0f2-2ef4eaa6b333" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent_01a0b014-d039-7b15-bc9a-2004142f3cee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent_01a0b014-d039-7b15-bc9a-2004142f3cee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_01a0aff5-dc01-7d08-a758-2b16e5b7fca4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_FinanceLeaseLiability_01a0aff5-dc01-7d08-a758-2b16e5b7fca4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a0aaff-906c-7e27-81a4-fb4b5b9fa55b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a0aaff-906c-7e27-81a4-fb4b5b9fa55b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_01a0affc-64b2-7994-80cf-293b0c2df84d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_01a0affc-64b2-7994-80cf-293b0c2df84d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_01a0aaff-906c-7525-8348-3e2d13035a39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_LongTermDebtCurrent_01a0aaff-906c-7525-8348-3e2d13035a39" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_01a0aaff-906c-7740-bd7c-710f07c1c237" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-778a-a10f-798a5d56b932" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_01a0aaff-906c-7740-bd7c-710f07c1c237" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/DebtandDerivativesNarrativeDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#DebtandDerivativesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/DebtandDerivativesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-7add-adc3-626132809688" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-7add-adc3-626132809688" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7add-adc3-626132809688_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-7add-adc3-626132809688" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7add-adc3-626132809688_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-7add-adc3-626132809688" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_TaxExemptBondsDue2055Member_01a0aaff-906c-7802-a38a-afc33d31206e" xlink:href="wm-20260930.xsd#wm_TaxExemptBondsDue2055Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_TaxExemptBondsDue2055Member_01a0aaff-906c-7802-a38a-afc33d31206e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CommercialPaperProgramMember_01a0aaff-906c-71ff-8d56-3a3b4ae9991f" xlink:href="wm-20260930.xsd#wm_CommercialPaperProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_CommercialPaperProgramMember_01a0aaff-906c-71ff-8d56-3a3b4ae9991f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_SeniorNotesDue2027Member_01a0b025-7017-7f01-9120-b9faeea62595" xlink:href="wm-20260930.xsd#wm_SeniorNotesDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_SeniorNotesDue2027Member_01a0b025-7017-7f01-9120-b9faeea62595" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c94e-9cda-77a0-ab09-8603983920ef" xlink:href="wm-20260930.xsd#wm_A3.5BillionRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c94e-9cda-77a0-ab09-8603983920ef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_OtherLetterOfCreditFacilitiesMember_01a0aaff-906c-7264-8fb7-ffe94d8c1799" xlink:href="wm-20260930.xsd#wm_OtherLetterOfCreditFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_OtherLetterOfCreditFacilitiesMember_01a0aaff-906c-7264-8fb7-ffe94d8c1799" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_SeniorNotesDue2026Member_01a0c97f-762b-774b-ab2b-aceb2c7675ad" xlink:href="wm-20260930.xsd#wm_SeniorNotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_SeniorNotesDue2026Member_01a0c97f-762b-774b-ab2b-aceb2c7675ad" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CanadianSeniorNotesDue2033Member_01a0c9ea-39ba-71bc-9330-a8a5b7a34797" xlink:href="wm-20260930.xsd#wm_CanadianSeniorNotesDue2033Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_CanadianSeniorNotesDue2033Member_01a0c9ea-39ba-71bc-9330-a8a5b7a34797" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CanadianSeniorNotesDue2026Member_01a0aaff-906c-7671-bdbf-27cadea0f003" xlink:href="wm-20260930.xsd#wm_CanadianSeniorNotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_CanadianSeniorNotesDue2026Member_01a0aaff-906c-7671-bdbf-27cadea0f003" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_FinancingLeasesAndOtherMember_01a130f4-2bde-767e-9926-91fd38f5ba0b" xlink:href="wm-20260930.xsd#wm_FinancingLeasesAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-7e19-af25-07722b98816f" xlink:to="loc_wm_FinancingLeasesAndOtherMember_01a130f4-2bde-767e-9926-91fd38f5ba0b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a0aaff-906c-79b2-900a-cfdfa9bb2244" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:to="loc_srt_RangeAxis_01a0aaff-906c-79b2-900a-cfdfa9bb2244" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-79b2-900a-cfdfa9bb2244_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-79b2-900a-cfdfa9bb2244" xlink:to="loc_srt_RangeMember_01a0aaff-906c-79b2-900a-cfdfa9bb2244_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0aaff-906c-7d70-83c7-1a02121c42b8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a0aaff-906c-79b2-900a-cfdfa9bb2244" xlink:to="loc_srt_RangeMember_01a0aaff-906c-7d70-83c7-1a02121c42b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a0aaff-906c-7cbe-93d6-c844e9687758" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-7d70-83c7-1a02121c42b8" xlink:to="loc_srt_MinimumMember_01a0aaff-906c-7cbe-93d6-c844e9687758" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a0aaff-906c-77e1-a628-7dacd97cd4d1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a0aaff-906c-7d70-83c7-1a02121c42b8" xlink:to="loc_srt_MaximumMember_01a0aaff-906c-77e1-a628-7dacd97cd4d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a0b027-2fb6-7c04-8088-be495ae464d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a0b027-2fb6-7c04-8088-be495ae464d5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7c04-8088-be495ae464d5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0b027-2fb6-7c04-8088-be495ae464d5" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7c04-8088-be495ae464d5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0b027-2fb6-7c04-8088-be495ae464d5" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BondsMember_01a0c9d9-eea9-77ee-8549-9b1eca8d0677" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_us-gaap_BondsMember_01a0c9d9-eea9-77ee-8549-9b1eca8d0677" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_01a0c97a-045c-7bfc-8ba2-271392d2fa9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_us-gaap_CommercialPaperMember_01a0c97a-045c-7bfc-8ba2-271392d2fa9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_01a0c9d9-eea9-797e-81b2-6666a1c97826" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_us-gaap_SeniorNotesMember_01a0c9d9-eea9-797e-81b2-6666a1c97826" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherDebtSecuritiesMember_01a0b027-2fb6-7960-8c4b-65145c5c6a31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_us-gaap_OtherDebtSecuritiesMember_01a0b027-2fb6-7960-8c4b-65145c5c6a31" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_01a0c94e-f06d-787f-a2d8-e29f64f3bf04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_us-gaap_LineOfCreditMember_01a0c94e-f06d-787f-a2d8-e29f64f3bf04" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CertainFixedRateSeniorNotesMember_01a17e62-0c7d-7b3c-a3bb-13650f8a9da3" xlink:href="wm-20260930.xsd#wm_CertainFixedRateSeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b027-2fb6-7348-a205-c59ce7b604ff" xlink:to="loc_wm_CertainFixedRateSeniorNotesMember_01a17e62-0c7d-7b3c-a3bb-13650f8a9da3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a0c94d-f86f-772a-86d5-3da10ebe81aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:to="loc_us-gaap_CreditFacilityAxis_01a0c94d-f86f-772a-86d5-3da10ebe81aa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c94d-f86f-772a-86d5-3da10ebe81aa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c94d-f86f-772a-86d5-3da10ebe81aa" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c94d-f86f-772a-86d5-3da10ebe81aa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c94d-f86f-7bf4-9aec-c4f456d8522d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c94d-f86f-772a-86d5-3da10ebe81aa" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c94d-f86f-7bf4-9aec-c4f456d8522d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a0c94e-223c-7e45-89f8-7da9c53cf6de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a0c94d-f86f-7bf4-9aec-c4f456d8522d" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a0c94e-223c-7e45-89f8-7da9c53cf6de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_01a15467-3dc6-75be-be3a-9aab54a8108f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a0aaff-906c-77db-b8d6-9b0f3aed47ef" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_01a15467-3dc6-75be-be3a-9aab54a8108f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a15467-3dc6-75be-be3a-9aab54a8108f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a15467-3dc6-75be-be3a-9aab54a8108f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a15467-3dc6-75be-be3a-9aab54a8108f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a15467-3dc6-7786-a4c4-d81f7e0cb7d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a15467-3dc6-75be-be3a-9aab54a8108f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a15467-3dc6-7786-a4c4-d81f7e0cb7d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_01a15467-621e-7018-90b6-00a3c089d76c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a15467-3dc6-7786-a4c4-d81f7e0cb7d6" xlink:to="loc_us-gaap_InterestRateSwapMember_01a15467-621e-7018-90b6-00a3c089d76c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRollingTwelveMonths_01a0b020-0b85-7e1c-b45d-f98a4a206243" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRollingTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRollingTwelveMonths_01a0b020-0b85-7e1c-b45d-f98a4a206243" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0aaff-906c-73a3-b454-cfbfb1b04863" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0aaff-906c-73a3-b454-cfbfb1b04863" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRolling12MonthsClassifiedAsLongTerm_01a0c99d-6caa-7deb-b6cf-7250dd8104a7" xlink:href="wm-20260930.xsd#wm_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRolling12MonthsClassifiedAsLongTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_wm_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextRolling12MonthsClassifiedAsLongTerm_01a0c99d-6caa-7deb-b6cf-7250dd8104a7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-7b72-9dbb-4fdabcbe1d1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-7b72-9dbb-4fdabcbe1d1f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtCurrent_01a0c9f1-ab63-7217-86bc-0d5245dbf3b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtCurrent_01a0c9f1-ab63-7217-86bc-0d5245dbf3b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a0aaff-906c-771d-9699-07795a418071" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a0aaff-906c-771d-9699-07795a418071" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_01a0aaff-906c-7885-83ec-58cd92992ddd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_LineOfCredit_01a0aaff-906c-7885-83ec-58cd92992ddd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_01a0aaff-906c-791a-937e-06be4171bf33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_01a0aaff-906c-791a-937e-06be4171bf33" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_01a0aaff-906c-7ecb-8ae2-946d67951dc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_01a0aaff-906c-7ecb-8ae2-946d67951dc3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_01a0c9e7-d4a6-7804-a815-5979b35980fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentTerm_01a0c9e7-d4a6-7804-a815-5979b35980fd" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfCommercialPaper_01a0c978-943c-7ee8-8e57-1c1d1cc73dd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfCommercialPaper"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_RepaymentsOfCommercialPaper_01a0c978-943c-7ee8-8e57-1c1d1cc73dd1" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommercialPaper_01a0c97a-621b-7822-9dbe-4d31e9a890e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfCommercialPaper"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommercialPaper_01a0c97a-621b-7822-9dbe-4d31e9a890e7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRepaidPrincipal_01a0c97e-b00f-7619-8f95-b84bcfde7b52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRepaidPrincipal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentRepaidPrincipal_01a0c97e-b00f-7619-8f95-b84bcfde7b52" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_01a0aaff-906c-79f2-80a8-2777450553b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_01a0aaff-906c-79f2-80a8-2777450553b9" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_01a0c982-204b-7d31-a47e-6eb3772ff4e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_01a0c982-204b-7d31-a47e-6eb3772ff4e2" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRepurchasedFaceAmount_01a15f43-995c-7548-9891-5ee7239d6820" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRepurchasedFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentRepurchasedFaceAmount_01a15f43-995c-7548-9891-5ee7239d6820" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet_01a130d6-24fb-77e2-96ff-e01d6d190de2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet_01a130d6-24fb-77e2-96ff-e01d6d190de2" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalLeaseObligationsIncurred_01a0c98c-fa88-7ee2-a23a-3a22684a173d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalLeaseObligationsIncurred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_CapitalLeaseObligationsIncurred_01a0c98c-fa88-7ee2-a23a-3a22684a173d" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebtAndCapitalSecurities_01a0c98c-78f7-784e-8456-086d00f137b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermDebtAndCapitalSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_RepaymentsOfLongTermDebtAndCapitalSecurities_01a0c98c-78f7-784e-8456-086d00f137b6" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_01a15466-f39b-768d-9fb7-b916740b6e75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DerivativeNotionalAmount_01a15466-f39b-768d-9fb7-b916740b6e75" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet_01a1546f-9786-7aec-aeed-8607796a7579" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a0aaff-906c-7c5b-a746-154f5c0b09f9" xlink:to="loc_us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet_01a1546f-9786-7aec-aeed-8607796a7579" xlink:type="arc" order="20"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/IncomeTaxesDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#IncomeTaxesDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/IncomeTaxesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:href="wm-20260930.xsd#wm_IncomeTaxesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_IncomeTaxesTable_01a0aaff-906c-7f0a-b543-ed21ed29ed34" xlink:href="wm-20260930.xsd#wm_IncomeTaxesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_wm_IncomeTaxesTable_01a0aaff-906c-7f0a-b543-ed21ed29ed34" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-906c-7d64-9647-cd23339d41f7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_wm_IncomeTaxesTable_01a0aaff-906c-7f0a-b543-ed21ed29ed34" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-906c-7d64-9647-cd23339d41f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7d64-9647-cd23339d41f7_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-906c-7d64-9647-cd23339d41f7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7d64-9647-cd23339d41f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7db6-9f63-8df59db66e47" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-906c-7d64-9647-cd23339d41f7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7db6-9f63-8df59db66e47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RenewableNaturalGasMember_01a0aaff-906c-768f-9962-75dc2618f9e5" xlink:href="wm-20260930.xsd#wm_RenewableNaturalGasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7db6-9f63-8df59db66e47" xlink:to="loc_wm_RenewableNaturalGasMember_01a0aaff-906c-768f-9962-75dc2618f9e5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_InvestmentInLowIncomeHousingPropertiesMember_01a0aaff-906c-7f90-b882-32f5a8c80ae7" xlink:href="wm-20260930.xsd#wm_InvestmentInLowIncomeHousingPropertiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-906c-7db6-9f63-8df59db66e47" xlink:to="loc_wm_InvestmentInLowIncomeHousingPropertiesMember_01a0aaff-906c-7f90-b882-32f5a8c80ae7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_01a111b7-856d-7c85-a715-b86257cca742" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_wm_IncomeTaxesTable_01a0aaff-906c-7f0a-b543-ed21ed29ed34" xlink:to="loc_us-gaap_TaxPeriodAxis_01a111b7-856d-7c85-a715-b86257cca742" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7c85-a715-b86257cca742_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_01a111b7-856d-7c85-a715-b86257cca742" xlink:to="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7c85-a715-b86257cca742_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7ac8-aef8-2da67a5b2148" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_01a111b7-856d-7c85-a715-b86257cca742" xlink:to="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7ac8-aef8-2da67a5b2148" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxYear2026Member_01a111b7-c2a3-7c8c-9dd5-9defcb11a0d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxYear2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7ac8-aef8-2da67a5b2148" xlink:to="loc_us-gaap_TaxYear2026Member_01a111b7-c2a3-7c8c-9dd5-9defcb11a0d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxYear2025Member_01a111b7-f71e-7198-b2b7-7dcf7e3e36d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxYear2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_01a111b7-856d-7ac8-aef8-2da67a5b2148" xlink:to="loc_us-gaap_TaxYear2025Member_01a111b7-f71e-7198-b2b7-7dcf7e3e36d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_01a0aaff-906c-798d-826b-16c6739dfdb9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_01a0aaff-906c-798d-826b-16c6739dfdb9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxCreditsAndAdjustments_01a0aaff-906c-7390-b954-d5b9317c4b37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxCreditsAndAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_us-gaap_IncomeTaxCreditsAndAdjustments_01a0aaff-906c-7390-b954-d5b9317c4b37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_IncomeTaxCreditsAndAdjustmentsProductionAndSalesActivity_01a0aaff-906c-7b52-9545-75dd81e31c73" xlink:href="wm-20260930.xsd#wm_IncomeTaxCreditsAndAdjustmentsProductionAndSalesActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_wm_IncomeTaxCreditsAndAdjustmentsProductionAndSalesActivity_01a0aaff-906c-7b52-9545-75dd81e31c73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentProgramProportionalAmortizationMethodElectedIncomeTaxCredit_01a0aaff-906c-77d7-b7cc-8dbc02bb385e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentProgramProportionalAmortizationMethodElectedIncomeTaxCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_us-gaap_InvestmentProgramProportionalAmortizationMethodElectedIncomeTaxCredit_01a0aaff-906c-77d7-b7cc-8dbc02bb385e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount_01a0aaff-906c-7b96-a374-caaa346297e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_us-gaap_AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount_01a0aaff-906c-7b96-a374-caaa346297e6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseBeneficialInterestsIssuedByConsolidatedVariableInterestEntities_01a0aaff-906c-7cdf-92f5-cb728b5f9eda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseBeneficialInterestsIssuedByConsolidatedVariableInterestEntities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_IncomeTaxesLineItems_01a0aaff-906c-7a0a-b814-4485bedbd0b4" xlink:to="loc_us-gaap_InterestExpenseBeneficialInterestsIssuedByConsolidatedVariableInterestEntities_01a0aaff-906c-7cdf-92f5-cb728b5f9eda" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/CommitmentsandContingenciesDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#CommitmentsandContingenciesDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/CommitmentsandContingenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-752f-908e-4a48b8433fa9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-752f-908e-4a48b8433fa9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c9a0-521a-728a-abd2-14575c1c811f" xlink:href="wm-20260930.xsd#wm_A3.5BillionRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:to="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c9a0-521a-728a-abd2-14575c1c811f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7b31-ab74-7cda64e1092f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7b31-ab74-7cda64e1092f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_SanJacintoWastePitsMember_01a0aaff-906c-7062-a2db-c6f94ff9c0c6" xlink:href="wm-20260930.xsd#wm_SanJacintoWastePitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:to="loc_wm_SanJacintoWastePitsMember_01a0aaff-906c-7062-a2db-c6f94ff9c0c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-70a6-9946-4de21eba11cf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-70a6-9946-4de21eba11cf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a0c9a0-521a-71dc-bada-78007c7b4471" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a0c9a0-521a-71dc-bada-78007c7b4471" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7135-9b0c-e8daa0ec9030_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7135-9b0c-e8daa0ec9030_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_01a0c9a0-521a-7e87-b6a5-1219f77ef04c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:to="loc_us-gaap_LineOfCreditMember_01a0c9a0-521a-7e87-b6a5-1219f77ef04c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-764d-86f5-d5598aa84b04_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:to="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-764d-86f5-d5598aa84b04_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:to="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxYear2017Member_01a0c9e4-9179-7b64-b278-1b1e75e9c9d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxYear2017Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:to="loc_us-gaap_TaxYear2017Member_01a0c9e4-9179-7b64-b278-1b1e75e9c9d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_01a0c9e4-9179-7f2b-89bf-5bc437822596" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfFinancialPositionLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_01a0c9e4-9179-7f2b-89bf-5bc437822596" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-703b-939b-104eb7cfdf53" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-703b-939b-104eb7cfdf53" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue_01a0aaff-906c-7084-b2d7-5822c9271d3d" xlink:href="wm-20260930.xsd#wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue_01a0aaff-906c-7084-b2d7-5822c9271d3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss_01a0aaff-906c-77ba-b6f4-a321924dd94f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss_01a0aaff-906c-77ba-b6f4-a321924dd94f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-7338-bf40-6f138939684b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccrualForEnvironmentalLossContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-7338-bf40-6f138939684b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7194-898b-f9f3bca152ca" xlink:href="wm-20260930.xsd#wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7194-898b-f9f3bca152ca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7a7a-846c-e8af87178c71" xlink:href="wm-20260930.xsd#wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7a7a-846c-e8af87178c71" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-75d3-946f-c36c321b9fa7" xlink:href="wm-20260930.xsd#wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-75d3-946f-c36c321b9fa7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage_01a0aaff-906c-71d7-96b7-b11c1435ff5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage_01a0aaff-906c-71d7-96b7-b11c1435ff5d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaid_01a0aaff-906c-7b02-98ec-515cf7c8bd7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxesPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_IncomeTaxesPaid_01a0aaff-906c-7b02-98ec-515cf7c8bd7f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIncomeTaxRefunds_01a0aaff-906c-79c2-bc07-b3e99cebde0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIncomeTaxRefunds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_ProceedsFromIncomeTaxRefunds_01a0aaff-906c-79c2-bc07-b3e99cebde0a" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_IrsDepositNetOfReserveForUncertainTaxPositions_01a0aaff-906c-7d5d-a5a0-c16d8cc553c2" xlink:href="wm-20260930.xsd#wm_IrsDepositNetOfReserveForUncertainTaxPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_IrsDepositNetOfReserveForUncertainTaxPositions_01a0aaff-906c-7d5d-a5a0-c16d8cc553c2" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/CommitmentsandContingenciesDetails_1" xlink:type="simple" xlink:href="wm-20260930.xsd#CommitmentsandContingenciesDetails_1"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/CommitmentsandContingenciesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-752f-908e-4a48b8433fa9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-752f-908e-4a48b8433fa9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a0aaff-906c-752f-908e-4a48b8433fa9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c9a0-521a-728a-abd2-14575c1c811f" xlink:href="wm-20260930.xsd#wm_A3.5BillionRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0aaff-906c-782e-81bb-a2202782c8d8" xlink:to="loc_wm_A3.5BillionRevolvingCreditFacilityMember_01a0c9a0-521a-728a-abd2-14575c1c811f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7b31-ab74-7cda64e1092f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7b31-ab74-7cda64e1092f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalRemediationSiteDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteAxis_01a0aaff-906c-7b31-ab74-7cda64e1092f" xlink:to="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_SanJacintoWastePitsMember_01a0aaff-906c-7062-a2db-c6f94ff9c0c6" xlink:href="wm-20260930.xsd#wm_SanJacintoWastePitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EnvironmentalRemediationSiteDomain_01a0aaff-906c-7f18-8687-cd477f9ce08f" xlink:to="loc_wm_SanJacintoWastePitsMember_01a0aaff-906c-7062-a2db-c6f94ff9c0c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-70a6-9946-4de21eba11cf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-70a6-9946-4de21eba11cf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a0c9a0-521a-70a6-9946-4de21eba11cf" xlink:to="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a0c9a0-521a-71dc-bada-78007c7b4471" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a0c9a0-521a-7a8c-927f-16061d41d919" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a0c9a0-521a-71dc-bada-78007c7b4471" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7135-9b0c-e8daa0ec9030_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7135-9b0c-e8daa0ec9030_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a0c9a0-521a-7135-9b0c-e8daa0ec9030" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_01a0c9a0-521a-7e87-b6a5-1219f77ef04c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0c9a0-521a-7663-90b3-4a943aef1d2e" xlink:to="loc_us-gaap_LineOfCreditMember_01a0c9a0-521a-7e87-b6a5-1219f77ef04c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a0aaff-906c-779f-92f7-6386ec15a7f5" xlink:to="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-764d-86f5-d5598aa84b04_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:to="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-764d-86f5-d5598aa84b04_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_01a0c9e4-9179-764d-86f5-d5598aa84b04" xlink:to="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxYear2017Member_01a0c9e4-9179-7b64-b278-1b1e75e9c9d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxYear2017Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_01a0c9e4-9179-7779-a736-6fd8704385bf" xlink:to="loc_us-gaap_TaxYear2017Member_01a0c9e4-9179-7b64-b278-1b1e75e9c9d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-703b-939b-104eb7cfdf53" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0aaff-906c-703b-939b-104eb7cfdf53" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue_01a0aaff-906c-7084-b2d7-5822c9271d3d" xlink:href="wm-20260930.xsd#wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfLandfillsAdjacentToOrNearHomeownersPropertiesWithAgreementsGuaranteeingMarketValue_01a0aaff-906c-7084-b2d7-5822c9271d3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss_01a0aaff-906c-77ba-b6f4-a321924dd94f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss_01a0aaff-906c-77ba-b6f4-a321924dd94f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-7338-bf40-6f138939684b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccrualForEnvironmentalLossContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_AccrualForEnvironmentalLossContingencies_01a0aaff-906c-7338-bf40-6f138939684b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7194-898b-f9f3bca152ca" xlink:href="wm-20260930.xsd#wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7194-898b-f9f3bca152ca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7a7a-846c-e8af87178c71" xlink:href="wm-20260930.xsd#wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-7a7a-846c-e8af87178c71" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-75d3-946f-c36c321b9fa7" xlink:href="wm-20260930.xsd#wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_NumberOfNonOwnedSitesListedOnEnvironmentalProtectionAgencyNationalPrioritiesListForWhichWeHaveBeenNotifiedWeArePrp_01a0aaff-906c-75d3-946f-c36c321b9fa7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage_01a0aaff-906c-71d7-96b7-b11c1435ff5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantEmployeesCoveredByCollectiveBargainingArrangementToAllParticipantsPercentage_01a0aaff-906c-71d7-96b7-b11c1435ff5d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaid_01a0aaff-906c-7b02-98ec-515cf7c8bd7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxesPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_IncomeTaxesPaid_01a0aaff-906c-7b02-98ec-515cf7c8bd7f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIncomeTaxRefunds_01a0aaff-906c-79c2-bc07-b3e99cebde0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIncomeTaxRefunds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_us-gaap_ProceedsFromIncomeTaxRefunds_01a0aaff-906c-79c2-bc07-b3e99cebde0a" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_IrsDepositNetOfReserveForUncertainTaxPositions_01a0aaff-906c-7d5d-a5a0-c16d8cc553c2" xlink:href="wm-20260930.xsd#wm_IrsDepositNetOfReserveForUncertainTaxPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a0aaff-906c-7e97-b5db-6cb62f6ae28f" xlink:to="loc_wm_IrsDepositNetOfReserveForUncertainTaxPositions_01a0aaff-906c-7d5d-a5a0-c16d8cc553c2" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/SegmentandRelatedInformationSummaryofFinancialInformationbyReportableSegmentDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#SegmentandRelatedInformationSummaryofFinancialInformationbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/SegmentandRelatedInformationSummaryofFinancialInformationbyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b51-b192-8a68f803e677" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b51-b192-8a68f803e677" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-76bf-928f-e0b127d9a54e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b51-b192-8a68f803e677" xlink:to="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-76bf-928f-e0b127d9a54e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-76bf-928f-e0b127d9a54e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-76bf-928f-e0b127d9a54e" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-76bf-928f-e0b127d9a54e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-719a-9370-ca561158935d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-76bf-928f-e0b127d9a54e" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-719a-9370-ca561158935d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-906c-783a-a059-35121b940221" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-719a-9370-ca561158935d" xlink:to="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-906c-783a-a059-35121b940221" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a0aaff-906c-7d0b-afd9-aa99da245f8d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-719a-9370-ca561158935d" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a0aaff-906c-7d0b-afd9-aa99da245f8d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-759c-8e53-3bd2e1710387" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b51-b192-8a68f803e677" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-759c-8e53-3bd2e1710387" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-906c-759c-8e53-3bd2e1710387_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-759c-8e53-3bd2e1710387" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-906c-759c-8e53-3bd2e1710387_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-759c-8e53-3bd2e1710387" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-70ab-a9d4-4cead935a190" xlink:href="wm-20260930.xsd#wm_CollectionAndDisposalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-70ab-a9d4-4cead935a190" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_EastTierMember_01a0aaff-906c-7119-9b41-ec96433ffd18" xlink:href="wm-20260930.xsd#wm_EastTierMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-70ab-a9d4-4cead935a190" xlink:to="loc_wm_EastTierMember_01a0aaff-906c-7119-9b41-ec96433ffd18" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_WestTierRegionAreasMember_01a0aaff-906c-74f1-a95e-7f9e603e0973" xlink:href="wm-20260930.xsd#wm_WestTierRegionAreasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-70ab-a9d4-4cead935a190" xlink:to="loc_wm_WestTierRegionAreasMember_01a0aaff-906c-74f1-a95e-7f9e603e0973" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_01a0aaff-906c-797f-9cde-16f730d390c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-70ab-a9d4-4cead935a190" xlink:to="loc_us-gaap_AllOtherSegmentsMember_01a0aaff-906c-797f-9cde-16f730d390c1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RecyclingProcessingAndSalesMember_01a0aaff-906c-7bf6-8b5f-6f1b1c2766d5" xlink:href="wm-20260930.xsd#wm_RecyclingProcessingAndSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_wm_RecyclingProcessingAndSalesMember_01a0aaff-906c-7bf6-8b5f-6f1b1c2766d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RenewableEnergySegmentMember_01a0aaff-906c-74e8-bfe6-822f5b111053" xlink:href="wm-20260930.xsd#wm_RenewableEnergySegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_wm_RenewableEnergySegmentMember_01a0aaff-906c-74e8-bfe6-822f5b111053" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_HealthcareSolutionsMember_01a0aaff-906c-7ac4-a175-0c12debbbd46" xlink:href="wm-20260930.xsd#wm_HealthcareSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_wm_HealthcareSolutionsMember_01a0aaff-906c-7ac4-a175-0c12debbbd46" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_01a0aaff-906c-7a69-9e71-2927cf31d48f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_us-gaap_CorporateAndOtherMember_01a0aaff-906c-7a69-9e71-2927cf31d48f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_EastTierWestTierAndCorporateAndOtherMember_01a11198-4095-7889-b970-88ec19af20f3" xlink:href="wm-20260930.xsd#wm_EastTierWestTierAndCorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-7005-955c-786c75cfd448" xlink:to="loc_wm_EastTierWestTierAndCorporateAndOtherMember_01a11198-4095-7889-b970-88ec19af20f3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a140a8-6270-7b6c-b456-28f1dd695339" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b51-b192-8a68f803e677" xlink:to="loc_srt_ProductOrServiceAxis_01a140a8-6270-7b6c-b456-28f1dd695339" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a140a8-6270-7b6c-b456-28f1dd695339_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a140a8-6270-7b6c-b456-28f1dd695339" xlink:to="loc_srt_ProductsAndServicesDomain_01a140a8-6270-7b6c-b456-28f1dd695339_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a140a8-6270-7496-87ad-81a89f9b9891" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a140a8-6270-7b6c-b456-28f1dd695339" xlink:to="loc_srt_ProductsAndServicesDomain_01a140a8-6270-7496-87ad-81a89f9b9891" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RecyclableMaterialFeeIncomeMember_01a140a8-ac33-7b93-91b7-140bd97df629" xlink:href="wm-20260930.xsd#wm_RecyclableMaterialFeeIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a140a8-6270-7496-87ad-81a89f9b9891" xlink:to="loc_wm_RecyclableMaterialFeeIncomeMember_01a140a8-ac33-7b93-91b7-140bd97df629" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_01a0aaff-906c-79b4-a681-209efa828830" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_NumberOfReportableSegments_01a0aaff-906c-79b4-a681-209efa828830" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_01a0aaff-906c-75f8-b9a3-9f4f342a2071" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_01a0aaff-906c-75f8-b9a3-9f4f342a2071" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_01a0aaff-906c-7adf-bb26-9376cef16b70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_01a0aaff-906c-7adf-bb26-9376cef16b70" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_01a0aaff-906c-752a-910e-75ab496ba7ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_01a0aaff-906c-752a-910e-75ab496ba7ef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_01a0aaff-906c-79a0-b282-9ae994e32277" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_01a0aaff-906c-79a0-b282-9ae994e32277" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_DepreciationDepletionAmortizationAndAccretion_01a0aaff-906c-766a-a39e-83d205802b2e" xlink:href="wm-20260930.xsd#wm_DepreciationDepletionAmortizationAndAccretion"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_wm_DepreciationDepletionAmortizationAndAccretion_01a0aaff-906c-766a-a39e-83d205802b2e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_01a0aaff-906c-700a-9a8c-758e2a28a165" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_OperatingIncomeLoss_01a0aaff-906c-700a-9a8c-758e2a28a165" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_01a0aaff-906c-74af-ac28-0b1a5cce8188" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentExpenditureAdditionToLongLivedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_01a0aaff-906c-74af-ac28-0b1a5cce8188" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RoyaltyPercentage_01a0aaff-906c-7176-bafb-dd166958267b" xlink:href="wm-20260930.xsd#wm_RoyaltyPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_wm_RoyaltyPercentage_01a0aaff-906c-7176-bafb-dd166958267b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RoyaltyExpense_01a0aaff-906c-7ae0-aaed-0397344c2cec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RoyaltyExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_us-gaap_RoyaltyExpense_01a0aaff-906c-7ae0-aaed-0397344c2cec" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RevenueFromCollectionAndDisposal_01a140b5-6c19-794b-8572-60185aa0693f" xlink:href="wm-20260930.xsd#wm_RevenueFromCollectionAndDisposal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_wm_RevenueFromCollectionAndDisposal_01a140b5-6c19-794b-8572-60185aa0693f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CollectionAndDisposalExpenses_01a140b5-0ab7-7c01-9be3-447858090588" xlink:href="wm-20260930.xsd#wm_CollectionAndDisposalExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-906c-7b29-9c76-351fb9c72f9d" xlink:to="loc_wm_CollectionAndDisposalExpenses_01a140b5-0ab7-7c01-9be3-447858090588" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/SegmentandRelatedInformationTotalAssetsbyReportableSegmentsDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#SegmentandRelatedInformationTotalAssetsbyReportableSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/SegmentandRelatedInformationTotalAssetsbyReportableSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-911a-75a2-9137-fc13b9fa9565" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b4f-a4b5-0cf94447e8e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-911a-75a2-9137-fc13b9fa9565" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b4f-a4b5-0cf94447e8e6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-7dcf-9ddb-e28db9b108ac" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b4f-a4b5-0cf94447e8e6" xlink:to="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-7dcf-9ddb-e28db9b108ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7dcf-9ddb-e28db9b108ac_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-7dcf-9ddb-e28db9b108ac" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7dcf-9ddb-e28db9b108ac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7172-90df-ea8494084dc3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-906c-7dcf-9ddb-e28db9b108ac" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7172-90df-ea8494084dc3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a0aaff-906c-7991-9283-2d520e47d789" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7172-90df-ea8494084dc3" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a0aaff-906c-7991-9283-2d520e47d789" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-906c-7a62-8ff4-699be6a79c29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-906c-7172-90df-ea8494084dc3" xlink:to="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-906c-7a62-8ff4-699be6a79c29" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-722b-aab3-f71dbe7e8d49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a0aaff-906c-7b4f-a4b5-0cf94447e8e6" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-722b-aab3-f71dbe7e8d49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-906c-722b-aab3-f71dbe7e8d49_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-722b-aab3-f71dbe7e8d49" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-906c-722b-aab3-f71dbe7e8d49_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-906c-722b-aab3-f71dbe7e8d49" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-793f-9bc4-3fe852f02af2" xlink:href="wm-20260930.xsd#wm_CollectionAndDisposalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:to="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-793f-9bc4-3fe852f02af2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_EastTierMember_01a0aaff-906c-7536-a652-a0a3edac8c9f" xlink:href="wm-20260930.xsd#wm_EastTierMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-793f-9bc4-3fe852f02af2" xlink:to="loc_wm_EastTierMember_01a0aaff-906c-7536-a652-a0a3edac8c9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_WestTierRegionAreasMember_01a0aaff-906c-7121-9983-754bcf0f54af" xlink:href="wm-20260930.xsd#wm_WestTierRegionAreasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-793f-9bc4-3fe852f02af2" xlink:to="loc_wm_WestTierRegionAreasMember_01a0aaff-906c-7121-9983-754bcf0f54af" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_01a0aaff-906c-7eb4-8ee8-bdebba31bc97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionAndDisposalMember_01a0aaff-906c-793f-9bc4-3fe852f02af2" xlink:to="loc_us-gaap_AllOtherSegmentsMember_01a0aaff-906c-7eb4-8ee8-bdebba31bc97" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RecyclingProcessingAndSalesMember_01a0aaff-906c-7bcc-ba32-54baa98617dd" xlink:href="wm-20260930.xsd#wm_RecyclingProcessingAndSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:to="loc_wm_RecyclingProcessingAndSalesMember_01a0aaff-906c-7bcc-ba32-54baa98617dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RenewableEnergySegmentMember_01a0aaff-911a-7133-b5b8-78beee003940" xlink:href="wm-20260930.xsd#wm_RenewableEnergySegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:to="loc_wm_RenewableEnergySegmentMember_01a0aaff-911a-7133-b5b8-78beee003940" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_HealthcareSolutionsMember_01a0aaff-911a-7c8c-8538-d9edad71e76b" xlink:href="wm-20260930.xsd#wm_HealthcareSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:to="loc_wm_HealthcareSolutionsMember_01a0aaff-911a-7c8c-8538-d9edad71e76b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_01a0aaff-911a-7111-aac2-e1c452989093" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-906c-734d-98f6-73d2e1d4a807" xlink:to="loc_us-gaap_CorporateAndOtherMember_01a0aaff-911a-7111-aac2-e1c452989093" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a0aaff-911a-703b-8718-18a0ff23bae5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a0aaff-911a-75a2-9137-fc13b9fa9565" xlink:to="loc_us-gaap_Assets_01a0aaff-911a-703b-8718-18a0ff23bae5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/SegmentandRelatedInformationScheduleofOperatingRevenuesDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#SegmentandRelatedInformationScheduleofOperatingRevenuesDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/SegmentandRelatedInformationScheduleofOperatingRevenuesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_01a0aaff-911a-7845-a5ef-7886ec019216" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_01a0aaff-911a-7c0b-a205-2ecf06264e29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_01a0aaff-911a-7845-a5ef-7886ec019216" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_01a0aaff-911a-7c0b-a205-2ecf06264e29" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a0aaff-911a-7a24-a196-0bc956558cf4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_01a0aaff-911a-7c0b-a205-2ecf06264e29" xlink:to="loc_srt_ConsolidationItemsAxis_01a0aaff-911a-7a24-a196-0bc956558cf4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7a24-a196-0bc956558cf4_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-911a-7a24-a196-0bc956558cf4" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7a24-a196-0bc956558cf4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7625-ae91-10cb8f949b84" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a0aaff-911a-7a24-a196-0bc956558cf4" xlink:to="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7625-ae91-10cb8f949b84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-911a-7a0f-9cd6-dd64ef390a75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7625-ae91-10cb8f949b84" xlink:to="loc_us-gaap_IntersegmentEliminationMember_01a0aaff-911a-7a0f-9cd6-dd64ef390a75" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a0aaff-911a-7249-8333-a6247038c951" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a0aaff-911a-7625-ae91-10cb8f949b84" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a0aaff-911a-7249-8333-a6247038c951" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a0aaff-911a-7d87-9d7c-424836594740" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_01a0aaff-911a-7c0b-a205-2ecf06264e29" xlink:to="loc_srt_ProductOrServiceAxis_01a0aaff-911a-7d87-9d7c-424836594740" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-7d87-9d7c-424836594740_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a0aaff-911a-7d87-9d7c-424836594740" xlink:to="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-7d87-9d7c-424836594740_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-732a-ae38-164661e916d4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a0aaff-911a-7d87-9d7c-424836594740" xlink:to="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-732a-ae38-164661e916d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:href="wm-20260930.xsd#wm_CollectionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-732a-ae38-164661e916d4" xlink:to="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CommercialMember_01a0aaff-911a-78e5-ba37-361470253f95" xlink:href="wm-20260930.xsd#wm_CommercialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:to="loc_wm_CommercialMember_01a0aaff-911a-78e5-ba37-361470253f95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_IndustrialMember_01a0aaff-911a-79c3-90c2-5288af726f9e" xlink:href="wm-20260930.xsd#wm_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:to="loc_wm_IndustrialMember_01a0aaff-911a-79c3-90c2-5288af726f9e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_ResidentialMember_01a0aaff-911a-7e79-877f-e76fa1cebd1a" xlink:href="wm-20260930.xsd#wm_ResidentialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:to="loc_wm_ResidentialMember_01a0aaff-911a-7e79-877f-e76fa1cebd1a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_OtherCollectionMember_01a0aaff-911a-7b96-8378-3d826ccf0655" xlink:href="wm-20260930.xsd#wm_OtherCollectionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wm_CollectionMember_01a0aaff-911a-7067-8c03-2d9b1acf5a0a" xlink:to="loc_wm_OtherCollectionMember_01a0aaff-911a-7b96-8378-3d826ccf0655" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandfillMember_01a0aaff-911a-75a2-9824-0d749a130605" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LandfillMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-732a-ae38-164661e916d4" xlink:to="loc_us-gaap_LandfillMember_01a0aaff-911a-75a2-9824-0d749a130605" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_TransferMember_01a0aaff-911a-7968-8db8-e54ba64ad990" xlink:href="wm-20260930.xsd#wm_TransferMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a0aaff-911a-732a-ae38-164661e916d4" xlink:to="loc_wm_TransferMember_01a0aaff-911a-7968-8db8-e54ba64ad990" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a0c478-2e1e-735e-ae46-fbfd78568fee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_01a0aaff-911a-7c0b-a205-2ecf06264e29" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a0c478-2e1e-735e-ae46-fbfd78568fee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0c478-2e1e-735e-ae46-fbfd78568fee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0c478-2e1e-735e-ae46-fbfd78568fee" xlink:to="loc_us-gaap_SegmentDomain_01a0c478-2e1e-735e-ae46-fbfd78568fee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0c478-2e1e-735e-ae46-fbfd78568fee" xlink:to="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CollectionAndDisposalMember_01a0c47c-8e3d-76e8-8422-5e29991fe321" xlink:href="wm-20260930.xsd#wm_CollectionAndDisposalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:to="loc_wm_CollectionAndDisposalMember_01a0c47c-8e3d-76e8-8422-5e29991fe321" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RecyclingProcessingAndSalesMember_01a0c47c-c67c-7f87-8a3c-7ed10a9ef233" xlink:href="wm-20260930.xsd#wm_RecyclingProcessingAndSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:to="loc_wm_RecyclingProcessingAndSalesMember_01a0c47c-c67c-7f87-8a3c-7ed10a9ef233" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RenewableEnergySegmentMember_01a0c47c-f338-7d6a-9fd7-05f0b5036b43" xlink:href="wm-20260930.xsd#wm_RenewableEnergySegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:to="loc_wm_RenewableEnergySegmentMember_01a0c47c-f338-7d6a-9fd7-05f0b5036b43" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_HealthcareSolutionsMember_01a0c47d-14fd-7141-9375-74705f1a2fcb" xlink:href="wm-20260930.xsd#wm_HealthcareSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:to="loc_wm_HealthcareSolutionsMember_01a0c47d-14fd-7141-9375-74705f1a2fcb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_01a0c478-2e1e-7660-9392-a9e915882abf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0c478-2e1e-7470-9712-e1c5e4e0b087" xlink:to="loc_us-gaap_CorporateAndOtherMember_01a0c478-2e1e-7660-9392-a9e915882abf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_01a0aaff-911a-7f7b-bf74-cc5442492403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_01a0aaff-911a-7845-a5ef-7886ec019216" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_01a0aaff-911a-7f7b-bf74-cc5442492403" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/AcquisitionsandDivestituresDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#AcquisitionsandDivestituresDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/AcquisitionsandDivestituresDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_01a0aaff-911a-7d55-81e9-bbd749b43563" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_01a0aaff-911a-7d55-81e9-bbd749b43563" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_01a0aaff-911a-79fc-b53a-1a973e20437d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_01a0aaff-911a-7d55-81e9-bbd749b43563" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_01a0aaff-911a-79fc-b53a-1a973e20437d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_01a0aaff-911a-79fc-b53a-1a973e20437d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_01a0aaff-911a-79fc-b53a-1a973e20437d" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_01a0aaff-911a-79fc-b53a-1a973e20437d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_01a0aaff-911a-7168-86b4-05b3cedec975" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_01a0aaff-911a-79fc-b53a-1a973e20437d" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_01a0aaff-911a-7168-86b4-05b3cedec975" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_01a0aaff-911a-7b25-9334-547ff08195f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_01a0aaff-911a-7168-86b4-05b3cedec975" xlink:to="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_01a0aaff-911a-7b25-9334-547ff08195f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-75f8-90e3-8f963fdc6df3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_01a0aaff-911a-7d55-81e9-bbd749b43563" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-75f8-90e3-8f963fdc6df3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-75f8-90e3-8f963fdc6df3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-75f8-90e3-8f963fdc6df3" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-75f8-90e3-8f963fdc6df3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-72b2-98a3-fa15dc7c3425" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-75f8-90e3-8f963fdc6df3" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-72b2-98a3-fa15dc7c3425" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0aaff-911a-7303-9ace-c465f227984e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-72b2-98a3-fa15dc7c3425" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0aaff-911a-7303-9ace-c465f227984e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-726f-837c-b01f0a863582" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_01a0aaff-911a-7d55-81e9-bbd749b43563" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-726f-837c-b01f0a863582" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-911a-726f-837c-b01f0a863582_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-726f-837c-b01f0a863582" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-911a-726f-837c-b01f0a863582_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-911a-733b-b325-7fdd207da0f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-726f-837c-b01f0a863582" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-911a-733b-b325-7fdd207da0f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_WestTierRegionAreasMember_01a0aaff-911a-74aa-82c3-4ca3f6dfc01b" xlink:href="wm-20260930.xsd#wm_WestTierRegionAreasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-911a-733b-b325-7fdd207da0f9" xlink:to="loc_wm_WestTierRegionAreasMember_01a0aaff-911a-74aa-82c3-4ca3f6dfc01b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_01a0aaff-911a-7af0-9f36-17b0ad7b0154" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_01a0aaff-911a-7af0-9f36-17b0ad7b0154" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_01a0c48c-3204-7206-88ff-7d49f9c923cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_01a0c48c-3204-7206-88ff-7d49f9c923cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_01a0aaff-911a-76c2-9fe2-96910505ced0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_01a0aaff-911a-76c2-9fe2-96910505ced0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherPaymentsToAcquireBusinesses_01a0aaff-911a-7af6-8adc-018e4d26d219" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherPaymentsToAcquireBusinesses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_OtherPaymentsToAcquireBusinesses_01a0aaff-911a-7af6-8adc-018e4d26d219" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities_01a0aaff-911a-7258-8a32-42a6612030b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities_01a0aaff-911a-7258-8a32-42a6612030b7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_01a0aaff-911a-769b-bad2-dbbdc5e5d8d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_01a0aaff-911a-769b-bad2-dbbdc5e5d8d0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_01a0aaff-911a-7612-8a31-7c2acb5e653c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_01a0aaff-911a-7612-8a31-7c2acb5e653c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_01a0aaff-911a-7f18-8bf4-3666f21e6b3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_Goodwill_01a0aaff-911a-7f18-8bf4-3666f21e6b3d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_ProceedsFromDivestitureOfBusinessesNetOfCashDivestedAndProceedsFromSalesOfAssetsInvestingActivities_01a130f3-31f4-721b-b45d-8ad5b2fb2cca" xlink:href="wm-20260930.xsd#wm_ProceedsFromDivestitureOfBusinessesNetOfCashDivestedAndProceedsFromSalesOfAssetsInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_wm_ProceedsFromDivestitureOfBusinessesNetOfCashDivestedAndProceedsFromSalesOfAssetsInvestingActivities_01a130f3-31f4-721b-b45d-8ad5b2fb2cca" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_01a17e6b-91db-7ccb-8eba-3394cdc7c11a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_01a0aaff-911a-7855-9444-e6bbbd52c68a" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_01a17e6b-91db-7ccb-8eba-3394cdc7c11a" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/GainLossfromDivestituresAssetImpairmentsandUnusualItemsNetDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#GainLossfromDivestituresAssetImpairmentsandUnusualItemsNetDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/GainLossfromDivestituresAssetImpairmentsandUnusualItemsNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusualOrInfrequentItemLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusualOrInfrequentItemTable_01a0aaff-911a-765b-b9b2-362500ef90c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusualOrInfrequentItemTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:to="loc_us-gaap_UnusualOrInfrequentItemTable_01a0aaff-911a-765b-b9b2-362500ef90c4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-707d-b411-9e3cd79cf77e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_UnusualOrInfrequentItemTable_01a0aaff-911a-765b-b9b2-362500ef90c4" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-707d-b411-9e3cd79cf77e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-707d-b411-9e3cd79cf77e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-707d-b411-9e3cd79cf77e" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-707d-b411-9e3cd79cf77e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-7d32-9d27-667863b45dd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0aaff-911a-707d-b411-9e3cd79cf77e" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-7d32-9d27-667863b45dd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0aaff-911a-75b8-8e99-a4d8d5692021" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_01a0aaff-911a-7d32-9d27-667863b45dd2" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0aaff-911a-75b8-8e99-a4d8d5692021" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-7c15-8413-c4e8d4650373" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_UnusualOrInfrequentItemTable_01a0aaff-911a-765b-b9b2-362500ef90c4" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-7c15-8413-c4e8d4650373" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-911a-7c15-8413-c4e8d4650373_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-7c15-8413-c4e8d4650373" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-911a-7c15-8413-c4e8d4650373_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a0aaff-911a-7c15-8413-c4e8d4650373" xlink:to="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RecyclingProcessingAndSalesMember_01a0c4b2-a4fa-72ff-9528-e8a682881c70" xlink:href="wm-20260930.xsd#wm_RecyclingProcessingAndSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:to="loc_wm_RecyclingProcessingAndSalesMember_01a0c4b2-a4fa-72ff-9528-e8a682881c70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_EastTierMember_01a0c4b3-e608-762e-8b87-3137d6d90001" xlink:href="wm-20260930.xsd#wm_EastTierMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:to="loc_wm_EastTierMember_01a0c4b3-e608-762e-8b87-3137d6d90001" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_RenewableEnergySegmentMember_01a11c92-bb8a-73fa-9b57-a027426ef544" xlink:href="wm-20260930.xsd#wm_RenewableEnergySegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:to="loc_wm_RenewableEnergySegmentMember_01a11c92-bb8a-73fa-9b57-a027426ef544" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_01a0c4b7-7bdf-731f-acc0-4ccb6bbf6122" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a0aaff-911a-7105-92a0-d06345424e98" xlink:to="loc_us-gaap_AllOtherSegmentsMember_01a0c4b7-7bdf-731f-acc0-4ccb6bbf6122" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_01a11191-379d-7935-b99e-75cba86c3f27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_01a11191-379d-7935-b99e-75cba86c3f27" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetImpairmentCharges_01a0aaff-911a-744e-b608-3c3f3a4224a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:to="loc_us-gaap_AssetImpairmentCharges_01a0aaff-911a-744e-b608-3c3f3a4224a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_GainLossFromDivestituresAssetImpairmentAndUnusualItems_01a0c4b4-8ef3-7d9d-9cb9-4add0e56e7ae" xlink:href="wm-20260930.xsd#wm_GainLossFromDivestituresAssetImpairmentAndUnusualItems"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:to="loc_wm_GainLossFromDivestituresAssetImpairmentAndUnusualItems_01a0c4b4-8ef3-7d9d-9cb9-4add0e56e7ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_01a11192-cb81-700c-b16b-36b0babe3f3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnusualOrInfrequentItemLineItems_01a0aaff-911a-7c61-8282-9c8180eb9ac9" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_01a11192-cb81-700c-b16b-36b0babe3f3c" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/AccumulatedOtherComprehensiveIncomeLossScheduleofAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#AccumulatedOtherComprehensiveIncomeLossScheduleofAccumulatedOtherComprehensiveIncomeLossDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/AccumulatedOtherComprehensiveIncomeLossScheduleofAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0aaff-911a-728d-b547-ce6e4d223fcf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0aaff-911a-77eb-a668-fcdc6d15c41b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0aaff-911a-728d-b547-ce6e4d223fcf" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0aaff-911a-77eb-a668-fcdc6d15c41b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-911a-7d26-8c64-91bc642f556b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0aaff-911a-77eb-a668-fcdc6d15c41b" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-911a-7d26-8c64-91bc642f556b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0aaff-911a-7d26-8c64-91bc642f556b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-911a-7d26-8c64-91bc642f556b" xlink:to="loc_us-gaap_EquityComponentDomain_01a0aaff-911a-7d26-8c64-91bc642f556b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0aaff-911a-7d92-b7ba-8e82c1adc190" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0aaff-911a-7d26-8c64-91bc642f556b" xlink:to="loc_us-gaap_EquityComponentDomain_01a0aaff-911a-7d92-b7ba-8e82c1adc190" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0aaff-911a-7d92-b7ba-8e82c1adc190" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_01a13b3b-dd6b-76bc-905e-c6d9489bf194" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_01a13b3b-dd6b-76bc-905e-c6d9489bf194" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_01a13b3c-5395-7408-ba13-b95828cbaf78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_01a13b3c-5395-7408-ba13-b95828cbaf78" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_01a13b3c-9801-77f9-89b7-c9e28663a3a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_01a13b3c-9801-77f9-89b7-c9e28663a3a6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_01a13b3c-f44e-7746-8de2-366b2c045257" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a13b3d-2955-7383-9738-7881f0a35b41" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_01a13b3c-f44e-7746-8de2-366b2c045257" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0aaff-911a-728d-b547-ce6e4d223fcf" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-911a-7972-b9a0-378b9245a5d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-911a-7972-b9a0-378b9245a5d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_01a0aaff-911a-7fef-998e-be6300427368" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_01a0aaff-911a-7fef-998e-be6300427368" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_01a0aaff-911a-75b3-9955-d5e5ad95cc45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_01a0aaff-911a-75b3-9955-d5e5ad95cc45" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_01a0aaff-911a-7127-b8c7-5aa60d624d85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_01a0aaff-911a-73b8-a0e6-ddd30f710f88" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_01a0aaff-911a-7127-b8c7-5aa60d624d85" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a0aaff-911a-7694-a968-12006babb01f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/AccumulatedOtherComprehensiveIncomeLossParentheticalDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#AccumulatedOtherComprehensiveIncomeLossParentheticalDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/AccumulatedOtherComprehensiveIncomeLossParentheticalDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0c4cc-2e78-7fc1-b397-78c4815b2356" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0c4cc-2e78-7478-8b59-ff5ae2508061" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0c4cc-2e78-7fc1-b397-78c4815b2356" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0c4cc-2e78-7478-8b59-ff5ae2508061" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_01a0c4cc-2e78-7a8f-aef5-f79554093559" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_01a0c4cc-2e78-7478-8b59-ff5ae2508061" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_01a0c4cc-2e78-7a8f-aef5-f79554093559" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7a8f-aef5-f79554093559_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0c4cc-2e78-7a8f-aef5-f79554093559" xlink:to="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7a8f-aef5-f79554093559_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a0c4cc-2e78-7a8f-aef5-f79554093559" xlink:to="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_01a13b3e-d09c-73a0-b94d-2009e40f947f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_01a13b3e-d09c-73a0-b94d-2009e40f947f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_01a13b3e-d09c-7b38-a5c5-9d2b5449cb05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_01a13b3e-d09c-7b38-a5c5-9d2b5449cb05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_01a13b3e-d09c-7c10-a501-df6c1fb51cd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_01a13b3e-d09c-7c10-a501-df6c1fb51cd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_01a13b3e-d09c-7b52-80a6-c5af084ccc92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a0c4cc-2e78-7351-b92f-7431c6e8d5c1" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_01a13b3e-d09c-7b52-80a6-c5af084ccc92" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_01a0c4cc-2e78-7066-9a15-6a66f14d1d4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0c4cc-2e78-7fc1-b397-78c4815b2356" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_01a0c4cc-2e78-7066-9a15-6a66f14d1d4e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_01a0c4cc-2e78-714b-a67b-5362bbeb9db1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_01a0c4cc-2e78-7fc1-b397-78c4815b2356" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_01a0c4cc-2e78-714b-a67b-5362bbeb9db1" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/CommonStockRepurchaseProgramDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#CommonStockRepurchaseProgramDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/CommonStockRepurchaseProgramDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityClassOfTreasuryStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfTreasuryStockTable_01a0aaff-911a-7186-97b6-c3ac0d86c38e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfTreasuryStockTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_us-gaap_ClassOfTreasuryStockTable_01a0aaff-911a-7186-97b6-c3ac0d86c38e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_01a0aaff-911a-7b35-8463-7093af4ddc52" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_01a0aaff-911a-7186-97b6-c3ac0d86c38e" xlink:to="loc_srt_ShareRepurchaseProgramAxis_01a0aaff-911a-7b35-8463-7093af4ddc52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-7b35-8463-7093af4ddc52_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a0aaff-911a-7b35-8463-7093af4ddc52" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-7b35-8463-7093af4ddc52_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-76ba-9885-b0b312b427e8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a0aaff-911a-7b35-8463-7093af4ddc52" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-76ba-9885-b0b312b427e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_AcceleratedShareRepurchaseAgreementMember_01a0c501-bcdd-7ce6-adad-bf3699a6e235" xlink:href="wm-20260930.xsd#wm_AcceleratedShareRepurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-76ba-9885-b0b312b427e8" xlink:to="loc_wm_AcceleratedShareRepurchaseAgreementMember_01a0c501-bcdd-7ce6-adad-bf3699a6e235" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_StockActivityUnder10b51PlanMember_01a0aaff-911a-79fd-bb6d-9f1a1f9c23a7" xlink:href="wm-20260930.xsd#wm_StockActivityUnder10b51PlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a0aaff-911a-76ba-9885-b0b312b427e8" xlink:to="loc_wm_StockActivityUnder10b51PlanMember_01a0aaff-911a-79fd-bb6d-9f1a1f9c23a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a0aaff-911a-77db-8439-8431e90db5fe" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a0aaff-911a-77db-8439-8431e90db5fe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a0c4fd-1305-72c1-a072-406e4f21b43d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a0c4fd-1305-72c1-a072-406e4f21b43d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_01a0aaff-911a-743d-adc2-a2918a4b4fa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_01a0aaff-911a-743d-adc2-a2918a4b4fa3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a0c4f8-4053-7f9a-9b10-b24ae9344398" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a0c4f8-4053-7f9a-9b10-b24ae9344398" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a0aaff-911a-74a6-bd28-c9c037f70c7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_01a0aaff-911a-7dbc-b00a-b47b667c4262" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a0aaff-911a-74a6-bd28-c9c037f70c7d" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/FairValueMeasurementsScheduleofAssetsandLiabilitiesMeasuredatFairValueDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#FairValueMeasurementsScheduleofAssetsandLiabilitiesMeasuredatFairValueDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/FairValueMeasurementsScheduleofAssetsandLiabilitiesMeasuredatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7ae0-99ad-e65e70e32377" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7ae0-99ad-e65e70e32377" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a0aaff-911a-75b6-ac53-64aa37b7b6e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7ae0-99ad-e65e70e32377" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a0aaff-911a-75b6-ac53-64aa37b7b6e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-75b6-ac53-64aa37b7b6e6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a0aaff-911a-75b6-ac53-64aa37b7b6e6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-75b6-ac53-64aa37b7b6e6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-7e70-b55b-6c0fb56945f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a0aaff-911a-75b6-ac53-64aa37b7b6e6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-7e70-b55b-6c0fb56945f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_01a0aaff-911a-7865-9bcc-930dc53d75e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-7e70-b55b-6c0fb56945f3" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_01a0aaff-911a-7865-9bcc-930dc53d75e6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_01a0aaff-911a-784a-84a4-440c0c038a87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a0aaff-911a-7e70-b55b-6c0fb56945f3" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_01a0aaff-911a-784a-84a4-440c0c038a87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_01a0aaff-911a-74b5-be22-ddbb1a50847b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_01a0aaff-911a-74b5-be22-ddbb1a50847b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent_01a0aaff-911a-707b-a6e3-a3b5e1d78f14" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent_01a0aaff-911a-707b-a6e3-a3b5e1d78f14" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_01a0c513-6965-7040-914e-c400453fafd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_01a0c513-6965-7040-914e-c400453fafd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_01a0aaff-911a-7a31-baeb-c4c38a053de8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_01a0aaff-911a-7a31-baeb-c4c38a053de8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a130e7-455e-724c-8eca-218c0d00e5bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_DerivativeLiabilities_01a130e7-455e-724c-8eca-218c0d00e5bd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_01a130e7-a2a8-709b-aa3f-37b8fbb7ff4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_01a130e7-a2a8-709b-aa3f-37b8fbb7ff4d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_InvestmentMaturityTerm_01a0c518-7151-7ee8-9f2b-2a1a24d12999" xlink:href="wm-20260930.xsd#wm_InvestmentMaturityTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-74c6-a614-8a34823c49b1" xlink:to="loc_wm_InvestmentMaturityTerm_01a0c518-7151-7ee8-9f2b-2a1a24d12999" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/FairValueMeasurementsNarrativeDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#FairValueMeasurementsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/FairValueMeasurementsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-7c4f-86d2-4b027a29a9d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7904-a4df-305a2d35cd65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-7c4f-86d2-4b027a29a9d3" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7904-a4df-305a2d35cd65" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_01a0aaff-911a-796f-8e88-9f5d8516497b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a0aaff-911a-7904-a4df-305a2d35cd65" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_01a0aaff-911a-796f-8e88-9f5d8516497b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-796f-8e88-9f5d8516497b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_01a0aaff-911a-796f-8e88-9f5d8516497b" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-796f-8e88-9f5d8516497b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_01a0aaff-911a-7f15-ab3f-22f3c640034c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_01a0aaff-911a-796f-8e88-9f5d8516497b" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_01a0aaff-911a-7f15-ab3f-22f3c640034c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-75c9-a032-d20016e93a7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_01a0aaff-911a-7f15-ab3f-22f3c640034c" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-75c9-a032-d20016e93a7c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_01a1117a-4f37-7cbd-8caf-bffecaefc635" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-75c9-a032-d20016e93a7c" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_01a1117a-4f37-7cbd-8caf-bffecaefc635" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_01a0aaff-911a-7b67-ac6b-13b817d967bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_01a0aaff-911a-75c9-a032-d20016e93a7c" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_01a0aaff-911a-7b67-ac6b-13b817d967bc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_01a11179-b289-747d-b048-098ee49f07e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a0aaff-911a-7c4f-86d2-4b027a29a9d3" xlink:to="loc_us-gaap_LongTermDebtFairValue_01a11179-b289-747d-b048-098ee49f07e7" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wm.com/role/VariableInterestEntitiesDetails" xlink:type="simple" xlink:href="wm-20260930.xsd#VariableInterestEntitiesDetails"/>
  <link:definitionLink xlink:role="http://www.wm.com/role/VariableInterestEntitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_01a0aaff-911a-77db-bd97-5f0ea23c49fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_01a0aaff-911a-799b-b250-64b57466b47b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_01a0aaff-911a-77db-bd97-5f0ea23c49fd" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_01a0aaff-911a-799b-b250-64b57466b47b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-911a-720a-bdb4-534021d5b6f3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_01a0aaff-911a-799b-b250-64b57466b47b" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-911a-720a-bdb4-534021d5b6f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-720a-bdb4-534021d5b6f3_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-911a-720a-bdb4-534021d5b6f3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-720a-bdb4-534021d5b6f3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-72e4-b704-af68b23f54e1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a0aaff-911a-720a-bdb4-534021d5b6f3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-72e4-b704-af68b23f54e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_InvestmentInLowIncomeHousingPropertiesMember_01a0aaff-911a-7f2b-a217-b3b966948545" xlink:href="wm-20260930.xsd#wm_InvestmentInLowIncomeHousingPropertiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-72e4-b704-af68b23f54e1" xlink:to="loc_wm_InvestmentInLowIncomeHousingPropertiesMember_01a0aaff-911a-7f2b-a217-b3b966948545" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_TrustForFinalCappingClosurePostClosureOrEnvironmentalRemediationObligationsMember_01a0aaff-911a-7301-bc2c-27668fefae36" xlink:href="wm-20260930.xsd#wm_TrustForFinalCappingClosurePostClosureOrEnvironmentalRemediationObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a0aaff-911a-72e4-b704-af68b23f54e1" xlink:to="loc_wm_TrustForFinalCappingClosurePostClosureOrEnvironmentalRemediationObligationsMember_01a0aaff-911a-7301-bc2c-27668fefae36" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_01a0aaff-911a-73f9-bd12-fbbd3bba493a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_01a0aaff-911a-799b-b250-64b57466b47b" xlink:to="loc_srt_ConsolidatedEntitiesAxis_01a0aaff-911a-73f9-bd12-fbbd3bba493a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-73f9-bd12-fbbd3bba493a_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_01a0aaff-911a-73f9-bd12-fbbd3bba493a" xlink:to="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-73f9-bd12-fbbd3bba493a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-740e-8718-e102f31c26bc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_01a0aaff-911a-73f9-bd12-fbbd3bba493a" xlink:to="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-740e-8718-e102f31c26bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_01a0aaff-911a-7c78-96cf-e81c7e12e3b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-740e-8718-e102f31c26bc" xlink:to="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_01a0aaff-911a-7c78-96cf-e81c7e12e3b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_01a0aaff-911a-7d0c-bcf9-b949975a57a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_01a0aaff-911a-740e-8718-e102f31c26bc" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_01a0aaff-911a-7d0c-bcf9-b949975a57a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_01a0aaff-911a-7843-912f-48d728c3b8c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_01a0aaff-911a-77db-bd97-5f0ea23c49fd" xlink:to="loc_us-gaap_EquityMethodInvestments_01a0aaff-911a-7843-912f-48d728c3b8c8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndCapitalLeaseObligations_01a0aaff-911a-7bf6-92f7-ac95d5fe97b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_01a0aaff-911a-77db-bd97-5f0ea23c49fd" xlink:to="loc_us-gaap_DebtAndCapitalLeaseObligations_01a0aaff-911a-7bf6-92f7-ac95d5fe97b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a0aaff-911a-7b31-95d2-1b75782f7e7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_01a0aaff-911a-77db-bd97-5f0ea23c49fd" xlink:to="loc_us-gaap_Assets_01a0aaff-911a-7b31-95d2-1b75782f7e7d" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_JohnJ.MorrisJr.Member_01a10cc5-fb5d-70dc-af9e-b58b11d46618" xlink:href="wm-20260930.xsd#wm_JohnJ.MorrisJr.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_wm_JohnJ.MorrisJr.Member_01a10cc5-fb5d-70dc-af9e-b58b11d46618" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_MichaelJ.WatsonMember_01a10cc8-305d-7fe5-9229-94de09ba5f47" xlink:href="wm-20260930.xsd#wm_MichaelJ.WatsonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_wm_MichaelJ.WatsonMember_01a10cc8-305d-7fe5-9229-94de09ba5f47" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CharlesBoettcherMember_01a0aaff-8eff-73d8-a93e-8d8bbd89e1d7" xlink:href="wm-20260930.xsd#wm_CharlesBoettcherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_wm_CharlesBoettcherMember_01a0aaff-8eff-73d8-a93e-8d8bbd89e1d7" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/TradingArrangementsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#TradingArrangmentsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/TradingArrangementsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllTradingArrangementsMember" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#ecd_AllTradingArrangementsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CharlesBoettcherTradingArrangementCommonStockMember_01a10cce-a219-793e-9160-7ff1b8960e6a" xlink:href="wm-20260930.xsd#wm_CharlesBoettcherTradingArrangementCommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllTradingArrangementsMember" xlink:to="loc_wm_CharlesBoettcherTradingArrangementCommonStockMember_01a10cce-a219-793e-9160-7ff1b8960e6a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wm_CharlesBoettcherTradingArrangementStockOptionsMember_01a10ccf-4b6b-780e-82d6-922a7b95ff90" xlink:href="wm-20260930.xsd#wm_CharlesBoettcherTradingArrangementStockOptionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllTradingArrangementsMember" xlink:to="loc_wm_CharlesBoettcherTradingArrangementStockOptionsMember_01a10ccf-4b6b-780e-82d6-922a7b95ff90" xlink:type="arc" order="2"/>
  </link:definitionLink>
</link:linkbase>
