dark glasses vs plural

dark glasses and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
dark glasses	Yes	No	No	No
plural	Yes	Yes	No	No

dark glasses (noun)	plural (noun)
(plural) spectacles that are darkened or polarized to protect the eyes from the glare of the sun	the form of a word that is used to denote more than one

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