dress whites vs plural

dress whites and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
dress whites	Yes	No	No	No
plural	Yes	Yes	No	No

dress whites (noun)	plural (noun)
a dress uniform for formal occasions	the form of a word that is used to denote more than one

dress whites (adjective)	plural (adjective)
	grammatical number category referring to two or more items or units
	composed of more than one member, set, or kind