The Collaborative International Dictionary of English v.0.48:

Fork \Fork\ (f[^o]rk), n. [AS. forc, fr. L. furca. Cf.
   Fourch['e], Furcate.]
   1. An instrument consisting of a handle with a shank
      terminating in two or more prongs or tines, which are
      usually of metal, parallel and slightly curved; -- used
      for piercing, holding, taking up, or pitching anything.
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   2. Anything furcate or like a fork in shape, or furcate at
      the extremity; as, a tuning fork.
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   3. One of the parts into which anything is furcated or
      divided; a prong; a branch of a stream, a road, etc.; a
      barbed point, as of an arrow.
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            Let it fall . . . though the fork invade
            The region of my heart.               --Shak.
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            A thunderbolt with three forks.       --Addison.
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   4. The place where a division or a union occurs; the angle or
      opening between two branches or limbs; as, the fork of a
      river, a tree, or a road.
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   5. The gibbet. [Obs.] --Bp. Butler.
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   Fork beam (Shipbuilding), a half beam to support a deck,
      where hatchways occur.

   Fork chuck (Wood Turning), a lathe center having two prongs
      for driving the work.

   Fork head.
      (a) The barbed head of an arrow.
      (b) The forked end of a rod which forms part of a knuckle
          joint.

   In fork. (Mining) A mine is said to be in fork, or an
      engine to "have the water in fork," when all the water is
      drawn out of the mine. --Ure.

   The forks of a river or The forks of a road, the branches
      into which it divides, or which come together to form it;
      the place where separation or union takes place.
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