beater vs carpet beater

beater and carpet beater both are nouns.

Word	Noun	Adjective	Verb	Adverb
beater	Yes	No	No	No
carpet beater	Yes	No	No	No

As nouns, carpet beater is a hyponym of beater; that is, carpet beater is a word with a more specific, narrower meaning than beater:

Other hyponyms of beater include rug beater, eggbeater, eggwhisk.

beater (noun)	carpet beater (noun)
an implement for beating	implement for beating dust out of carpets
a worker who rouses wild game from under cover for a hunter