public works vs plural

public works and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
public works	Yes	No	No	No
plural	Yes	Yes	No	No

public works (noun)	plural (noun)
structures (such as highways or schools or bridges or docks) constructed at government expense for public use	the form of a word that is used to denote more than one

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