"MP3 CD" meaning in English

{
  "forms": [
    {
      "form": "MP3 CDs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "MP3 CD (plural MP3 CDs)",
      "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": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2005, Brian Tiemann, iPod + iTunes for Windows and Mac in a Snap, page 207:",
          "text": "More and more car audio systems entering the market today support MP3 CDs, and just about all commercial DVD players do as well—it's become a ubiquitous technology.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A CD-ROM containing compressed audio tracks, often, but not always in the MP3 format."
      ],
      "id": "en-MP3_CD-en-noun-UI7fgGPp",
      "links": [
        [
          "CD-ROM",
          "CD-ROM"
        ],
        [
          "MP3",
          "MP3"
        ]
      ]
    }
  ],
  "word": "MP3 CD"
}

{
  "forms": [
    {
      "form": "MP3 CDs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "MP3 CD (plural MP3 CDs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with numbers",
        "English terms with quotations",
        "English words without vowels",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "ref": "2005, Brian Tiemann, iPod + iTunes for Windows and Mac in a Snap, page 207:",
          "text": "More and more car audio systems entering the market today support MP3 CDs, and just about all commercial DVD players do as well—it's become a ubiquitous technology.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A CD-ROM containing compressed audio tracks, often, but not always in the MP3 format."
      ],
      "links": [
        [
          "CD-ROM",
          "CD-ROM"
        ],
        [
          "MP3",
          "MP3"
        ]
      ]
    }
  ],
  "word": "MP3 CD"
}