week from Monday vs colloquialism

week from Monday and colloquialism both are nouns.

Word	Noun	Adjective	Verb	Adverb
week from Monday	Yes	No	No	No
colloquialism	Yes	No	No	No

week from Monday (noun)	colloquialism (noun)
a time period of a week or more	a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech