repeat vs repeater

repeat and repeater both are nouns.

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

repeat (noun)	repeater (noun)
an event that repeats	a firearm that can fire several rounds without reloading
	(electronics) electronic device that amplifies a signal before transmitting it again
	a person who repeats
	someone who is repeatedly arrested for criminal behavior (especially for the same criminal behavior)

repeat (verb)	repeater (verb)
happen or occur again
to say, state, or perform again
to say again or imitate
make or do or perform again
repeat an earlier theme of a composition
do over