colloquialism vs number one

colloquialism and number one both are nouns.

Word	Noun	Adjective	Verb	Adverb
colloquialism	Yes	No	No	No
number one	Yes	No	No	No

colloquialism (noun)	number one (noun)
a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech	a reference to yourself or myself etc.; `take care of number one' means to put your own interests first
	the first element in a countable series
	the first or highest in an ordering or series