"thermal mass" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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        "Synonym of heat capacity"
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        "(thermodynamics) Synonym of heat capacity"
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  "word": "thermal mass"
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{
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    {
      "form": "thermal masses",
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Synonym of heat capacity"
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        "(thermodynamics) Synonym of heat capacity"
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  "word": "thermal mass"
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