first-rate vs colloquialism

first-rate is not a noun while colloquialism is a noun.

Word	Noun	Adjective	Verb	Adverb
first-rate	No	Yes	No	Yes
colloquialism	Yes	No	No	No

first-rate (noun)	colloquialism (noun)
	a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech

first-rate (adjective)	colloquialism (adjective)
of the highest quality

first-rate (adverb)	colloquialism (adverb)
quite well