dirty tricks vs plural

dirty tricks and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
dirty tricks	Yes	No	No	No
plural	Yes	Yes	No	No

dirty tricks (noun)	plural (noun)
underhand commercial or political behavior designed to discredit an opponent	the form of a word that is used to denote more than one

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