The Collaborative International Dictionary of English v.0.48:

Heck \Heck\, n. [See Hatch a half door.] [Written also
   hack.]
   1. The bolt or latch of a door. [Prov. Eng.]
      [1913 Webster]

   2. A rack for cattle to feed at. [Prov. Eng.]
      [1913 Webster]

   3. A door, especially one partly of latticework; -- called
      also heck door. [Prov. Eng.] --Halliwell.
      [1913 Webster]

   4. A latticework contrivance for catching fish.
      [1913 Webster]

   5. (Weaving) An apparatus for separating the threads of warps
      into sets, as they are wound upon the reel from the
      bobbins, in a warping machine.
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   6. A bend or winding of a stream. [Prov. Eng.]
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   Half heck, the lower half of a door.

   Heck board, the loose board at the bottom or back of a
      cart.

   Heck box or Heck frame, that which carries the heck in
      warping.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Heck \Heck\, n.
   hell; -- a euphemism. Used commonly in the phrase "What the
   heck". [Colloq.]
   [PJC]