Source : Webster's Revised Unabridged Dictionary (1913)

Tuyere \Tu`y[`e]re"\, n. [F.; akin to tuyau a pipe; of Teutonic
   origin. Cf. {Tweer}, {Tewel}.]
   A nozzle, mouthpiece, or fixture through which the blast is
   delivered to the interior of a blast furnace, or to the fire
   of a forge. [Corruptly written also {tweer}, and {twier}.]

   {Tuy[`e]re arch}, the embrasure, in the wall of a blast
      furnace through which the tuy[`e]re enters.