insignificant vs colloquialism

insignificant is not a noun while colloquialism is a noun.

Word	Noun	Adjective	Verb	Adverb
insignificant	No	Yes	No	No
colloquialism	Yes	No	No	No

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

insignificant (adjective)	colloquialism (adjective)
devoid of importance, meaning, or force
signifying nothing
of little importance or influence or power; of minor status
small and unimpressive