"D4" meaning in French

{
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "noun"
      },
      "expansion": "D4",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "fr",
          "name": "Dice games",
          "orig": "fr:Dice games",
          "parents": [
            "Tabletop games",
            "Games",
            "Recreation",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "d4"
      ],
      "id": "en-D4-fr-noun-rzJ6ZHhT",
      "links": [
        [
          "dice game",
          "dice game"
        ],
        [
          "d4",
          "d4"
        ]
      ],
      "raw_glosses": [
        "(dice games) d4"
      ],
      "synonyms": [
        {
          "word": "dé à quatre faces"
        }
      ],
      "topics": [
        "dice",
        "games"
      ]
    }
  ],
  "word": "D4"
}

{
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "noun"
      },
      "expansion": "D4",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "French entries with incorrect language header",
        "French lemmas",
        "French nouns",
        "French terms spelled with numbers",
        "fr:Dice games"
      ],
      "glosses": [
        "d4"
      ],
      "links": [
        [
          "dice game",
          "dice game"
        ],
        [
          "d4",
          "d4"
        ]
      ],
      "raw_glosses": [
        "(dice games) d4"
      ],
      "synonyms": [
        {
          "word": "dé à quatre faces"
        }
      ],
      "topics": [
        "dice",
        "games"
      ]
    }
  ],
  "word": "D4"
}