"Cb" meaning in Translingual

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  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
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      "glosses": [
        "Obsolete chemical symbol for columbium, now named niobium."
      ],
      "id": "en-Cb-mul-symbol-maglRug6",
      "links": [
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          "chemistry",
          "chemistry"
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          "obsolete",
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        [
          "columbium",
          "columbium#English"
        ],
        [
          "niobium",
          "niobium#English"
        ]
      ],
      "raw_glosses": [
        "(chemistry, obsolete) Obsolete chemical symbol for columbium, now named niobium."
      ],
      "synonyms": [
        {
          "word": "Nb"
        }
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        "obsolete"
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      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
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  "word": "Cb"
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  "lang_code": "mul",
  "pos": "symbol",
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        "Obsolete symbols for chemical elements",
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        "Obsolete chemical symbol for columbium, now named niobium."
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          "columbium",
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          "niobium",
          "niobium#English"
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        "(chemistry, obsolete) Obsolete chemical symbol for columbium, now named niobium."
      ],
      "synonyms": [
        {
          "word": "Nb"
        }
      ],
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        "obsolete"
      ],
      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
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  ],
  "word": "Cb"
}