flattop vs attack aircraft carrier

flattop and attack aircraft carrier both are nouns.

Word	Noun	Adjective	Verb	Adverb
flattop	Yes	No	No	No
attack aircraft carrier	Yes	No	No	No

As nouns, flattop and attack aircraft carrier are synonyms defined as:

flattop and attack aircraft carrier: a large warship that carries planes and has a long flat deck for takeoffs and landings

Other synonyms of flattop include aircraft carrier, carrier.

flattop (noun)	attack aircraft carrier (noun)
a large warship that carries planes and has a long flat deck for takeoffs and landings	a large warship that carries planes and has a long flat deck for takeoffs and landings
a closely cropped haircut; usually for men or boys