minor expense vs plural

minor expense and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
minor expense	Yes	No	No	No
plural	Yes	Yes	No	No

minor expense (noun)	plural (noun)
(frequently plural) an expense not budgeted or not specified	the form of a word that is used to denote more than one

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