slip-joint pliers vs plural

slip-joint pliers and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
slip-joint pliers	Yes	No	No	No
plural	Yes	Yes	No	No

slip-joint pliers (noun)	plural (noun)
pliers with a joint adjustable to two positions in order to increase the opening of the jaws	the form of a word that is used to denote more than one

slip-joint pliers (adjective)	plural (adjective)
	grammatical number category referring to two or more items or units
	composed of more than one member, set, or kind