colloquialism vs flatfooted

colloquialism is a noun but flatfooted is not a noun.

Word	Noun	Adjective	Verb	Adverb
colloquialism	Yes	No	No	No
flatfooted	No	Yes	No	No

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

colloquialism (adjective)	flatfooted (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