swimsuit vs swimwear

swimsuit and swimwear both are nouns.

Word	Noun	Adjective	Verb	Adverb
swimsuit	Yes	No	No	No
swimwear	Yes	No	No	No

As nouns, swimsuit and swimwear are synonyms defined as:

Other synonyms of swimsuit include bathing costume, bathing suit, swimming costume.

swimsuit (noun)	swimwear (noun)
tight fitting garment worn for swimming	tight fitting garment worn for swimming