"GMT" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Greenwich Mean Time"
        }
      ],
      "categories": [
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          "name": "English entries with incorrect language header",
          "parents": [
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Time",
          "orig": "en:Time",
          "parents": [
            "All topics",
            "Fundamental"
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          "source": "w"
        }
      ],
      "glosses": [
        "Initialism of Greenwich Mean Time."
      ],
      "id": "en-GMT-en-name-mQ8B7Ddz",
      "links": [
        [
          "Greenwich Mean Time",
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      "synonyms": [
        {
          "word": "UTC"
        }
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      "tags": [
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        "alt-of",
        "initialism"
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  "word": "GMT"
}

{
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    {
      "args": {},
      "expansion": "GMT",
      "name": "en-proper noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Greenwich Mean Time"
        }
      ],
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        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English initialisms",
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        "English proper nouns",
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        "en:Time"
      ],
      "glosses": [
        "Initialism of Greenwich Mean Time."
      ],
      "links": [
        [
          "Greenwich Mean Time",
          "Greenwich Mean Time#English"
        ]
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        "abbreviation",
        "alt-of",
        "initialism"
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  "synonyms": [
    {
      "word": "UTC"
    }
  ],
  "word": "GMT"
}