The Collaborative International Dictionary of English v.0.48:

Forcing \For"cing\, n.
   1. The accomplishing of any purpose violently, precipitately,
      prematurely, or with unusual expedition.
      [1913 Webster]

   2. (Gardening) The art of raising plants, flowers, and fruits
      at an earlier season than the natural one, as in a hitbed
      or by the use of artificial heat.
      [1913 Webster]

   Forcing bed or Forcing pit, a plant bed having an under
      layer of fermenting manure, the fermentation yielding
      bottom heat for forcing plants; a hotbed.

   Forcing engine, a fire engine.

   Forcing fit (Mech.), a tight fit, as of one part into a
      hole in another part, which makes it necessary to use
      considerable force in putting the two parts together.

   Forcing house, a greenhouse for the forcing of plants,
      fruit trees, etc.

   Forcing machine, a powerful press for putting together or
      separating two parts that are fitted tightly one into
      another, as for forcing a crank on a shaft, or for drawing
      off a car wheel from the axle.

   Forcing pump. See Force pump
      (b) .
          [1913 Webster]