adj

• (archaic) Made of brass.
  "Brazen or rather copper swords seem to have been next introduced; these in process of time, workmen learned to harden by the addition of some other metal or mineral, which rendered them almost equal in temper to iron."
• (figuratively) Brass-like in appearance or character; bright, ruddy, hard.
  "The women, stout, strong, brazen-faced creatures, in most cases looked able to thrash any of the partners with whom they consorted."
• (archaic) Extremely strong; impenetrable; resolute.
  "The giant [Goliath] was thus conquered by the youth [David]; the man-at-arms by the unarmed; the stone of the shepherd pierced the brazen defences of the warrior."

verb

• (intransitive) To turn a brass color.
  "[...] the meadows roughen, grow gutteral / with goldenrod, milkweed's late-summer lilac, / cat-tails, the wild lily brazening, / dooryards overflowing in late, rough-headed bloom: [...]"
• (transitive) Generally followed by out or through: to carry through in a brazen manner; to act boldly despite embarrassment, risk, etc.
  "And though the word doth eat up all they can ſay, as Moſes rod did: yet they harden their hearts with Pharaoh, they brazen their brows with him in the text, that ſaid I will not: Nay ſaid the Iſraelites, but we will have a King. [Commentary on Matthew 21:29.]"