Source : Webster's Revised Unabridged Dictionary (1913)

Jet \Jet\, n. [F. jet, OF. get, giet, L. jactus a throwing, a
   throw, fr. jacere to throw. Cf. {Abject}, {Ejaculate},
   {Gist}, {Jess}, {Jut}.]
   1. A shooting forth; a spouting; a spurt; a sudden rush or
      gush, as of water from a pipe, or of flame from an
      orifice; also, that which issues in a jet.

   2. Drift; scope; range, as of an argument. [Obs.]

   3. The sprue of a type, which is broken from it when the type
      is cold. --Knight.

   {Jet propeller} (Naut.), a device for propelling vessels by
      means of a forcible jet of water ejected from the vessel,
      as by a centrifugal pump.

   {Jet pump}, a device in which a small jet of steam, air,
      water, or other fluid, in rapid motion, lifts or otherwise
      moves, by its impulse, a larger quantity of the fluid with
      which it mingles.