Brazen
Old English bræsen ‘made of brass’, from bræs ‘brass’, of unknown ultimate origin.
wiktionary
From Middle English brasen, from Old English bræsen(“brazen, of brass”); equivalent to brass + -en (compare golden). [1]
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 bold as brass.
etymonline
brazen (adj.)
Old English bræsen "of brass," from bræs "brass" (see brass (n.)) + -en (2). The figurative sense of "hardened in effrontery" is from 1570s (in brazen-faced), perhaps suggesting a face unable to show shame. To brazen it "face impudently" is from 1550s. Related: Brazenly.
