videodisk A form of read-only optical disk, devised for recording TV programs but also used for education and training. A write-once version is also available. Videodisks have been used for recording data, particularly when it is in image form, for computer systems; CD-ROM or DVD is now preferred for most such applications.

video disc Vinyl disc coated with a reflective, metallic surfacing. On one side of the reflective surface is etched a spiral of microscopic pits corresponding to digital information that can be picked up by a laser scanner and converted electronically to video pictures and sound. Since the late 1980s, video discs have been almost entirely superseded by the smaller, more comprehensive type of compact disc (CD) called a CD-ROM.

vid·e·o·disc / ˈvidēōˌdisk/ (also vid·e·o·disk) • n. a CD-ROM or other disk used to store visual images and sound.