Meaning

verb face with defiance or impudence

adjective unrestrained by convention or propriety; ; ; - Los Angeles Times; ; ; - Bertrand Russell

adjective made of or resembling brass (as in color or hardness)

originFrom Middle English brasen, from Old English bræsen (“brazen, of brass”); equivalent to brass + -en (compare golden, wooden, etc.). The word originally meant “of brass”; the figurative verb sense (as in brazen it out (“face impudently”)) dates from the 1550s (perhaps evoking the sense “face like brass, unmoving and not showing shame”), and the adjective sense “impudent” from the 1570s. Compare…

Etymology from Wiktionary, CC BY-SA 3.0