"case hardening" meaning in English

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  "lang_code": "en",
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        "present participle and gerund of case harden"
      ],
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          "case harden#English"
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  "wikipedia": [
    "case hardening"
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  "word": "case hardening"
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      "expansion": "case hardening (uncountable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Metallurgy",
          "orig": "en:Metallurgy",
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            "Metals",
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      "glosses": [
        "The process of imparting greater hardness to the surface of a piece of metal."
      ],
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          "hard",
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          "surface",
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          "metal",
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        "(metallurgy) The process of imparting greater hardness to the surface of a piece of metal."
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        "uncountable"
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        "engineering",
        "metallurgy",
        "natural-sciences",
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    {
      "glosses": [
        "A condition of dried meat in which the exterior is so dry and hard that the interior moisture is sealed in."
      ],
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  "wikipedia": [
    "case hardening"
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  "word": "case hardening"
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        "present participle and gerund of case harden"
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        "The process of imparting greater hardness to the surface of a piece of metal."
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        "(metallurgy) The process of imparting greater hardness to the surface of a piece of metal."
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      ],
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      ]
    }
  ],
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    "case hardening"
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