brave vs audacious

brave is a noun but audacious is not a noun.

Word	Noun	Adjective	Verb	Adverb
brave	Yes	Yes	Yes	No
audacious	No	Yes	No	No

As adjectives, brave and audacious are synonyms defined as:

Other synonyms of brave include dauntless, fearless, hardy, intrepid, unfearing.

brave (noun)	audacious (noun)
people who are brave
a North American Indian warrior

brave (adjective)	audacious (adjective)
possessing or displaying courage; able to face and deal with danger or fear without flinching	disposed to venture or take risks
invulnerable to fear or intimidation	invulnerable to fear or intimidation
brightly colored and showy	unrestrained by convention or propriety

brave (verb)	audacious (verb)
face and withstand with courage