brevity vs brief

brevity and brief both are nouns.

Word	Noun	Adjective	Verb	Adverb
brevity	Yes	No	No	No
brief	Yes	Yes	Yes	No

brevity (noun)	brief (noun)
the attribute of being brief or fleeting	a condensed written summary or abstract
the use of brief expressions	a document stating the facts and points of law of a client's case

brevity (adjective)	brief (adjective)
	concise and succinct
	(of clothing) very short
	of short duration or distance

brevity (verb)	brief (verb)
	give essential information to someone