flat-footed vs colloquialism

flat-footed is not a noun while colloquialism is a noun.

Word	Noun	Adjective	Verb	Adverb
flat-footed	No	Yes	No	No
colloquialism	Yes	No	No	No

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

flat-footed (adjective)	colloquialism (adjective)
forthright and explicit
with feet flat on the ground; not tiptoe
having broad flat feet that usually turn outward
unprepared and unable to react quickly