plural vs stacks

plural and stacks both are nouns.

Word	Noun	Adjective	Verb	Adverb
plural	Yes	Yes	No	No
stacks	Yes	No	No	No

plural (noun)	stacks (noun)
the form of a word that is used to denote more than one	storage space in a library consisting of an extensive arrangement of bookshelves where most of the books are stored
	a large number or amount

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