"WW1" meaning in English

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  "head_templates": [
    {
      "args": {},
      "expansion": "WW1",
      "name": "en-proper noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "World War I"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "History of the United States",
          "orig": "en:History of the United States",
          "parents": [
            "United States",
            "History",
            "North America",
            "All topics",
            "America",
            "Fundamental",
            "Earth",
            "Nature"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "War",
          "orig": "en:War",
          "parents": [
            "Conflict",
            "Military",
            "Violence",
            "Human behaviour",
            "Society",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Abbreviation of World War I."
      ],
      "id": "en-WW1-en-name-RbV8fHKp",
      "links": [
        [
          "World War I",
          "World War I#English"
        ]
      ],
      "synonyms": [
        {
          "word": "WWI"
        }
      ],
      "tags": [
        "abbreviation",
        "alt-of"
      ],
      "wikipedia": [
        "WW1"
      ]
    }
  ],
  "word": "WW1"
}

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      "args": {},
      "expansion": "WW1",
      "name": "en-proper noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "World War I"
        }
      ],
      "categories": [
        "English abbreviations",
        "English entries with incorrect language header",
        "English lemmas",
        "English proper nouns",
        "English terms spelled with numbers",
        "English uncountable nouns",
        "English words without vowels",
        "Pages with 1 entry",
        "Pages with entries",
        "en:History of the United States",
        "en:War"
      ],
      "glosses": [
        "Abbreviation of World War I."
      ],
      "links": [
        [
          "World War I",
          "World War I#English"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of"
      ],
      "wikipedia": [
        "WW1"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "WWI"
    }
  ],
  "word": "WW1"
}