colloquialism vs frightful

colloquialism is a noun but frightful is not a noun.

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

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

colloquialism (adjective)	frightful (adjective)
	provoking horror
	extremely distressing
	extreme in degree or extent or amount or impact