compact disc

small disk used for storing computerized information (i.e. computer programs, music, etc.)

A Compact Disc or CD is an optical disc used to store digital data, originally developed for storing digital audio. The CD, available on the market since late 1982, remains the standard playback medium for commercial audio recordings to the present day, although it has lost ground in recent years to MP3 players, which have greater storage capability, albeit with noticeably lower sound quality in most cases.
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<storage> (CD) (Not "disk", this spelling is part of the standard).
A 4.72 inch disc developed by Sony and Philips that can store, on the same disc, still and/or moving images in monochrome and/or color; stereo or two separate sound tracks integrated with and/or separate from the images; and digital program and information files.
The same fabrication process is used to make both audio CDs and CD-ROMs for storing computer data, the only difference is in the device used to read the CD (the player or drive).
CD Information Center.
(1999-06-23)

Noun
1. a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser
(synonym) compact disk, CD
(hypernym) optical disk, optical disc
(hyponym) audio CD, audio compact disc