videodisc vs videodisk

videodisc and videodisk both are nouns.

Word	Noun	Adjective	Verb	Adverb
videodisc	Yes	No	No	No
videodisk	Yes	No	No	No

As nouns, videodisc and videodisk are synonyms defined as:

videodisc and videodisk: a digital recording (as of a movie) on an optical disk that can be played on a computer or a television set

Other synonyms of videodisc include DVD.

videodisc (noun)	videodisk (noun)
a digital recording (as of a movie) on an optical disk that can be played on a computer or a television set	a digital recording (as of a movie) on an optical disk that can be played on a computer or a television set