bikini pants vs plural form

bikini pants and plural form both are nouns.

Word	Noun	Adjective	Verb	Adverb
bikini pants	Yes	No	No	No
plural form	Yes	No	No	No

bikini pants (noun)	plural form (noun)
(used in the plural) small and tight-fitting underpants; worn by women	the form of a word that is used to denote more than one