forty winks vs colloquialism

forty winks and colloquialism both are nouns.

Word	Noun	Adjective	Verb	Adverb
forty winks	Yes	No	No	No
colloquialism	Yes	No	No	No

forty winks (noun)	colloquialism (noun)
sleeping for a short period of time (usually not in bed)	a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech