audio CD vs audio compact disc

audio CD and audio compact disc both are nouns.

Word	Noun	Adjective	Verb	Adverb
audio CD	Yes	No	No	No
audio compact disc	Yes	No	No	No

As nouns, audio CD and audio compact disc are synonyms defined as:

audio CD and audio compact disc: compact discs used to reproduce sound (voice and music)

audio CD (noun)	audio compact disc (noun)
compact discs used to reproduce sound (voice and music)	compact discs used to reproduce sound (voice and music)