"pyrophoric alloy" meaning in English

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      "form": "pyrophoric alloys",
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      "expansion": "pyrophoric alloy (plural pyrophoric alloys)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Alloys",
          "orig": "en:Alloys",
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            "Metallurgy",
            "Chemistry",
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      ],
      "glosses": [
        "An alloy, especially one of iron or cerium, that emits sparks when scratched or struck."
      ],
      "id": "en-pyrophoric_alloy-en-noun-2Ju5thNc",
      "links": [
        [
          "iron",
          "iron"
        ],
        [
          "cerium",
          "cerium"
        ],
        [
          "spark",
          "spark"
        ],
        [
          "scratch",
          "scratch"
        ],
        [
          "struck",
          "struck"
        ]
      ]
    }
  ],
  "word": "pyrophoric alloy"
}

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      "form": "pyrophoric alloys",
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  "lang_code": "en",
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      "glosses": [
        "An alloy, especially one of iron or cerium, that emits sparks when scratched or struck."
      ],
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        [
          "iron",
          "iron"
        ],
        [
          "cerium",
          "cerium"
        ],
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          "spark"
        ],
        [
          "scratch",
          "scratch"
        ],
        [
          "struck",
          "struck"
        ]
      ]
    }
  ],
  "word": "pyrophoric alloy"
}