colloquialism vs wet blanket

colloquialism and wet blanket both are nouns.

Word	Noun	Adjective	Verb	Adverb
colloquialism	Yes	No	No	No
wet blanket	Yes	No	No	No

colloquialism (noun)	wet blanket (noun)
a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech	someone who spoils the pleasure of others