colloquialism vs forty winks

colloquialism and forty winks both are nouns.

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

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