knockout drops vs plural

knockout drops and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
knockout drops	Yes	No	No	No
plural	Yes	Yes	No	No

knockout drops (noun)	plural (noun)
chloral hydrate in combination with alcohol; usually administered surreptitiously to make the drinker unconscious	the form of a word that is used to denote more than one

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