The Collaborative International Dictionary of English v.0.48:

Bridle \Bri"dle\, n. [OE. bridel, AS. bridel; akin to OHG.
   britil, brittil, D. breidel, and possibly to E. braid. Cf.
   Bridoon.]
   1. The head gear with which a horse is governed and
      restrained, consisting of a headstall, a bit, and reins,
      with other appendages.
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   2. A restraint; a curb; a check. --I. Watts.
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   3. (Gun.) The piece in the interior of a gun lock, which
      holds in place the tumbler, sear, etc.
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   4. (Naut.)
      (a) A span of rope, line, or chain made fast as both ends,
          so that another rope, line, or chain may be attached
          to its middle.
      (b) A mooring hawser.
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   Bowline bridle. See under Bowline.

   Branches of a bridle. See under Branch.

   Bridle cable (Naut.), a cable which is bent to a bridle.
      See 4, above.

   Bridle hand, the hand which holds the bridle in riding; the
      left hand.

   Bridle path, Bridle way, a path or way for saddle horses
      and pack horses, as distinguished from a road for
      vehicles.

   Bridle port (Naut.), a porthole or opening in the bow
      through which hawsers, mooring or bridle cables, etc., are
      passed.

   Bridle rein, a rein attached to the bit.

   Bridle road.
      (a) Same as Bridle path. --Lowell.
      (b) A road in a pleasure park reserved for horseback
          exercise.

   Bridle track, a bridle path.

   Scolding bridle. See Branks, 2.
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   Syn: A check; restrain.
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