waterworks vs plural form

waterworks and plural form both are nouns.

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

waterworks (noun)	plural form (noun)
workplace where water is stored and purified and distributed for a community	the form of a word that is used to denote more than one
a public utility that provides water