gown vs apparel

gown and apparel both are nouns.

Word	Noun	Adjective	Verb	Adverb
gown	Yes	No	Yes	No
apparel	Yes	No	Yes	No

As verbs, apparel is a hypernym of gown; that is, apparel is a word with a broader meaning than gown:

Other hypernyms of gown include clothe, dress, enclothe, fit out, garb, garment, habilitate, raiment, tog.

gown (noun)	apparel (noun)
a woman's dress, usually with a close-fitting bodice and a long flared skirt, often worn on formal occasions	clothing in general
outerwear consisting of a long flowing garment used for official or ceremonial occasions
protective garment worn by surgeons during operations
lingerie consisting of a loose dress designed to be worn in bed by women
the members of a university as distinguished from the other residents of the town in which the university is located

gown (verb)	apparel (verb)
dress in a gown	provide with clothes or put clothes on