swimsuit vs maillot

swimsuit and maillot both are nouns.

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

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

Other hyponyms of swimsuit include bikini, two-piece, tank suit, bathing trunks, swimming trunks.

swimsuit (noun)	maillot (noun)
tight fitting garment worn for swimming	tights for dancers or gymnasts
	a woman's one-piece bathing suit