The Collaborative International Dictionary of English v.0.48:

Heel \Heel\, n. [OE. hele, heele, AS. h[=e]la, perh. for
   h[=o]hila, fr. AS. h[=o]h heel (cf. Hough); but cf. D.
   hiel, OFries. heila, h[=e]la, Icel. h[ae]ll, Dan. h[ae]l, Sw.
   h[aum]l, and L. calx. [root]12. Cf. Inculcate.]
   1. The hinder part of the foot; sometimes, the whole foot; --
      in man or quadrupeds.
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            He [the stag] calls to mind his strength and then
            his speed,
            His winged heels and then his armed head. --Denham.
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   2. The hinder part of any covering for the foot, as of a
      shoe, sock, etc.; specif., a solid part projecting
      downward from the hinder part of the sole of a boot or
      shoe.
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   3. The latter or remaining part of anything; the closing or
      concluding part. "The heel of a hunt." --A. Trollope. "The
      heel of the white loaf." --Sir W. Scott.
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   4. Anything regarded as like a human heel in shape; a
      protuberance; a knob.
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   5. The part of a thing corresponding in position to the human
      heel; the lower part, or part on which a thing rests;
      especially:
      (a) (Naut.) The after end of a ship's keel.
      (b) (Naut.) The lower end of a mast, a boom, the bowsprit,
          the sternpost, etc.
      (c) (Mil.) In a small arm, the corner of the but which is
          upwards in the firing position.
      (d) (Mil.) The uppermost part of the blade of a sword,
          next to the hilt.
      (e) The part of any tool next the tang or handle; as, the
          heel of a scythe.
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   6. (Man.) Management by the heel, especially the spurred
      heel; as, the horse understands the heel well.
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   7. (Arch.)
      (a) The lower end of a timber in a frame, as a post or
          rafter. In the United States, specif., the obtuse
          angle of the lower end of a rafter set sloping.
      (b) A cyma reversa; -- so called by workmen. --Gwilt.
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   8. (Golf) The part of the face of the club head nearest the
      shaft.
      [Webster 1913 Suppl.]

   9. In a carding machine, the part of a flat nearest the
      cylinder.
      [Webster 1913 Suppl.]

   Heel chain (Naut.), a chain passing from the bowsprit cap
      around the heel of the jib boom.

   Heel plate, the butt plate of a gun.

   Heel of a rafter. (Arch.) See Heel, n., 7.

   Heel ring, a ring for fastening a scythe blade to the
      snath.

   Neck and heels, the whole body. (Colloq.)

   To be at the heels of, to pursue closely; to follow hard;
      as, hungry want is at my heels. --Otway.

   To be down at the heel, to be slovenly or in a poor plight.


   To be out at the heels, to have on stockings that are worn
      out; hence, to be shabby, or in a poor plight. --Shak.

   To cool the heels. See under Cool.

   To go heels over head, to turn over so as to bring the
      heels uppermost; hence, to move in a inconsiderate, or
      rash, manner.

   To have the heels of, to outrun.

   To lay by the heels, to fetter; to shackle; to imprison.
      --Shak. --Addison.

   To show the heels, to flee; to run from.

   To take to the heels, to flee; to betake to flight.

   To throw up another's heels, to trip him. --Bunyan.

   To tread upon one's heels, to follow closely. --Shak.
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