videodisk vs DVD

videodisk and DVD both are nouns.

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

As nouns, videodisk and DVD are synonyms defined as:

videodisk and DVD: 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 videodisk include videodisc.

videodisk (noun)	DVD (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