"M81" meaning in English

{
  "etymology_text": "From M (used for model) + 81 (short for 1981, the year of its introduction), following the pattern of the Model designation for U.S. military equipment.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "M81 (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English words spelled without vowels",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "The woodland camouflage pattern used by the United States Armed Forces from 1981 until 2012."
      ],
      "id": "en-M81-en-noun-WqNv4I3b",
      "links": [
        [
          "military",
          "military"
        ],
        [
          "woodland",
          "woodland"
        ],
        [
          "camouflage",
          "camouflage"
        ]
      ],
      "raw_glosses": [
        "(military slang) The woodland camouflage pattern used by the United States Armed Forces from 1981 until 2012."
      ],
      "tags": [
        "slang",
        "uncountable"
      ],
      "topics": [
        "government",
        "military",
        "politics",
        "war"
      ]
    }
  ],
  "word": "M81"
}

{
  "etymology_text": "From M (used for model) + 81 (short for 1981, the year of its introduction), following the pattern of the Model designation for U.S. military equipment.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "M81 (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English military slang",
        "English nouns",
        "English terms spelled with numbers",
        "English uncountable nouns",
        "English words spelled without vowels",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "glosses": [
        "The woodland camouflage pattern used by the United States Armed Forces from 1981 until 2012."
      ],
      "links": [
        [
          "military",
          "military"
        ],
        [
          "woodland",
          "woodland"
        ],
        [
          "camouflage",
          "camouflage"
        ]
      ],
      "raw_glosses": [
        "(military slang) The woodland camouflage pattern used by the United States Armed Forces from 1981 until 2012."
      ],
      "tags": [
        "slang",
        "uncountable"
      ],
      "topics": [
        "government",
        "military",
        "politics",
        "war"
      ]
    }
  ],
  "word": "M81"
}