replay vs repeat

replay and repeat both are nouns.

Word	Noun	Adjective	Verb	Adverb
replay	Yes	No	Yes	No
repeat	Yes	No	Yes	No

As nouns, repeat is a hypernym of replay; that is, repeat is a word with a broader meaning than replay:

Other hypernyms of replay include repetition.

replay (noun)	repeat (noun)
the immediate rebroadcast of some action (especially sports action) that has been recorded on videotape	an event that repeats
something (especially a game) that is played again

replay (verb)	repeat (verb)
play again	happen or occur again
repeat a game against the same opponent	to say, state, or perform again
play (a melody) again	to say again or imitate
reproduce (a recording) on a recorder	make or do or perform again
	repeat an earlier theme of a composition
	do over