"milk acid" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Carboxylic acids",
          "orig": "en:Carboxylic acids",
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      "glosses": [
        "acid of milk, lactic acid"
      ],
      "id": "en-milk_acid-en-noun-R21zzw7B",
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          "organic chemistry",
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        [
          "acid of milk",
          "acid of milk"
        ],
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          "lactic acid",
          "lactic acid"
        ]
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      "raw_glosses": [
        "(obsolete, organic chemistry) acid of milk, lactic acid"
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  "word": "milk acid"
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "acid of milk, lactic acid"
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          "acid of milk",
          "acid of milk"
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        "(obsolete, organic chemistry) acid of milk, lactic acid"
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  "word": "milk acid"
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