Cut-off /(kŭt"ŏf`; 115)/

Cut·-off

Cut-off

n.
  1. That which cuts off or shortens, as a nearer passage or road.
  2. 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. (Mach.)