gym suit vs sportswear

gym suit and sportswear both are nouns.

Word	Noun	Adjective	Verb	Adverb
gym suit	Yes	No	No	No
sportswear	Yes	No	No	No

As nouns, sportswear is a hypernym of gym suit; that is, sportswear is a word with a broader meaning than gym suit:

gym suit: clothes prescribed for wear while participating in gymnastic exercise
sportswear: attire worn for sport or for casual wear

Other hypernyms of gym suit include activewear, athletic wear.

gym suit (noun)	sportswear (noun)
clothes prescribed for wear while participating in gymnastic exercise	attire worn for sport or for casual wear