sourpuss vs colloquialism

sourpuss and colloquialism both are nouns.

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

sourpuss (noun)	colloquialism (noun)
someone with a habitually sullen or gloomy expression	a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech