"MP4 player" meaning in English

{
  "forms": [
    {
      "form": "MP4 players",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "MP4 player (plural MP4 players)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Electronics",
          "orig": "en:Electronics",
          "parents": [
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "An electronic device for playing digital audio files in the MP4 format (and, in many cases, also files in other formats)."
      ],
      "id": "en-MP4_player-en-noun-ZkC7tyOo",
      "links": [
        [
          "electronic",
          "electronic"
        ],
        [
          "MP4",
          "MP4"
        ]
      ]
    }
  ],
  "word": "MP4 player"
}

{
  "forms": [
    {
      "form": "MP4 players",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "MP4 player (plural MP4 players)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with numbers",
        "English terms with non-redundant non-automated sortkeys",
        "en:Electronics"
      ],
      "glosses": [
        "An electronic device for playing digital audio files in the MP4 format (and, in many cases, also files in other formats)."
      ],
      "links": [
        [
          "electronic",
          "electronic"
        ],
        [
          "MP4",
          "MP4"
        ]
      ]
    }
  ],
  "word": "MP4 player"
}