"passive iron" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Iron that has been subjected to the action of heat, strong nitric acid, chlorine, etc. It is then not easily acted upon by acids."
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      "id": "en-passive_iron-en-noun-q0ikQ58z",
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          "nitric acid",
          "nitric acid"
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          "chlorine",
          "chlorine"
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        "(chemistry) Iron that has been subjected to the action of heat, strong nitric acid, chlorine, etc. It is then not easily acted upon by acids."
      ],
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      "topics": [
        "chemistry",
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  "word": "passive iron"
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  "lang_code": "en",
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      "glosses": [
        "Iron that has been subjected to the action of heat, strong nitric acid, chlorine, etc. It is then not easily acted upon by acids."
      ],
      "links": [
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          "chemistry",
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        [
          "nitric acid",
          "nitric acid"
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          "chlorine",
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        "(chemistry) Iron that has been subjected to the action of heat, strong nitric acid, chlorine, etc. It is then not easily acted upon by acids."
      ],
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  "word": "passive iron"
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