"14-18 war" meaning in English

{
  "etymology_text": "From the years in which the war was fought, 1914 to 1918.",
  "head_templates": [
    {
      "args": {},
      "expansion": "14-18 war",
      "name": "en-proper noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "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": "World War I",
          "orig": "en:World War I",
          "parents": [
            "Historical events",
            "History of Europe",
            "War",
            "History",
            "Europe",
            "Conflict",
            "Military",
            "Violence",
            "All topics",
            "Earth",
            "Eurasia",
            "Human behaviour",
            "Society",
            "Fundamental",
            "Nature",
            "Human"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "World War I."
      ],
      "id": "en-14-18_war-en-name-hl9v1iFB",
      "links": [
        [
          "World War I",
          "World War I"
        ]
      ],
      "raw_glosses": [
        "(informal) World War I."
      ],
      "synonyms": [
        {
          "word": "'14-'18"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "14-18 war"
}

{
  "etymology_text": "From the years in which the war was fought, 1914 to 1918.",
  "head_templates": [
    {
      "args": {},
      "expansion": "14-18 war",
      "name": "en-proper noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English proper nouns",
        "English terms spelled with numbers",
        "English uncountable nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "en:World War I"
      ],
      "glosses": [
        "World War I."
      ],
      "links": [
        [
          "World War I",
          "World War I"
        ]
      ],
      "raw_glosses": [
        "(informal) World War I."
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "'14-'18"
    }
  ],
  "word": "14-18 war"
}