by all means vs colloquialism

by all means is not a noun while colloquialism is a noun.

Word	Noun	Adjective	Verb	Adverb
by all means	No	No	No	Yes
colloquialism	Yes	No	No	No

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

by all means (adverb)	colloquialism (adverb)
definitely or certainly