"hydrogenium" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "name": "Hydrogen",
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      "glosses": [
        "Hydrogen, especially when formerly considered as a metal."
      ],
      "id": "en-hydrogenium-en-noun-5MX95k51",
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        [
          "Hydrogen",
          "hydrogen"
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        "(obsolete) Hydrogen, especially when formerly considered as a metal."
      ],
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        "uncountable"
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  "word": "hydrogenium"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Hydrogen, especially when formerly considered as a metal."
      ],
      "links": [
        [
          "Hydrogen",
          "hydrogen"
        ],
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          "metal",
          "metal"
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        "(obsolete) Hydrogen, especially when formerly considered as a metal."
      ],
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        "obsolete",
        "uncountable"
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  "word": "hydrogenium"
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