"GCA" meaning in English

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      "form": "GCAs",
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      "expansion": "GCA (plural GCAs)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "greatest common ancestor"
        }
      ],
      "categories": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "source": "w"
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          "name": "Pages with 2 entries",
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          "source": "w"
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        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Graph theory",
          "orig": "en:Graph theory",
          "parents": [
            "Mathematics",
            "Visualization",
            "Formal sciences",
            "Computing",
            "Interdisciplinary fields",
            "Sciences",
            "Technology",
            "All topics",
            "Fundamental"
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          "source": "w"
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      ],
      "glosses": [
        "Initialism of greatest common ancestor."
      ],
      "id": "en-GCA-en-noun-a8pnm2B7",
      "links": [
        [
          "graph theory",
          "graph theory"
        ],
        [
          "greatest common ancestor",
          "greatest common ancestor#English"
        ]
      ],
      "raw_glosses": [
        "(graph theory) Initialism of greatest common ancestor."
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "initialism"
      ],
      "topics": [
        "graph-theory",
        "mathematics",
        "sciences"
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    }
  ],
  "word": "GCA"
}

{
  "forms": [
    {
      "form": "GCAs",
      "tags": [
        "plural"
      ]
    }
  ],
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      "expansion": "GCA (plural GCAs)",
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  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "word": "greatest common ancestor"
        }
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      "glosses": [
        "Initialism of greatest common ancestor."
      ],
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        [
          "graph theory",
          "graph theory"
        ],
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          "greatest common ancestor",
          "greatest common ancestor#English"
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      ],
      "raw_glosses": [
        "(graph theory) Initialism of greatest common ancestor."
      ],
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        "initialism"
      ],
      "topics": [
        "graph-theory",
        "mathematics",
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    }
  ],
  "word": "GCA"
}