stacks vs plural form

stacks and plural form both are nouns.

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

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