overdress vs apparel

overdress is not a noun while apparel is a noun.

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

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

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

overdress (noun)	apparel (noun)
	clothing in general

overdress (verb)	apparel (verb)
put on special clothes to appear particularly appealing and attractive	provide with clothes or put clothes on
dress too warmly