Source : Webster's Revised Unabridged Dictionary (1913)

Cut-off \Cut"-off`\ (k[u^]t"[o^]f`; 115), n.
   1. That which cuts off or shortens, as a nearer passage or
      road.

   2. (Mach.)
      (a) The valve gearing or mechanism by which steam is cut
          off from entering the cylinder of a steam engine after
          a definite point in a stroke, so as to allow the
          remainder of the stroke to be made by the expansive
          force of the steam already let in. See {Expansion
          gear}, under {Expansion}.
      (b) Any device for stopping or changing a current, as of
          grain or water in a spout.