like mad vs colloquialism

like mad is not a noun while colloquialism is a noun.

Word	Noun	Adjective	Verb	Adverb
like mad	No	No	No	Yes
colloquialism	Yes	No	No	No

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

like mad (adverb)	colloquialism (adverb)
(informal) with great speed or effort or intensity; used for emphasis