plural vs field glasses

plural and field glasses both are nouns.

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

plural (noun)	field glasses (noun)
the form of a word that is used to denote more than one	(plural) an optical instrument designed for simultaneous use by both eyes

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