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.
1. The head gear with which a horse is governed and
restrained, consisting of a headstall, a bit, and reins,
with other appendages.
2. A restraint; a curb; a check. --I. Watts.
3. (Gun.) The piece in the interior of a gun lock, which
holds in place the tumbler, sear, etc.
(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.
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
Bridle path, Bridle way, a path or way for saddle horses
and pack horses, as distinguished from a road for
Bridle port (Naut.), a porthole or opening in the bow
through which hawsers, mooring or bridle cables, etc., are
Bridle rein, a rein attached to the bit.
(a) Same as Bridle path. --Lowell.
(b) A road in a pleasure park reserved for horseback
Bridle track, a bridle path.
Scolding bridle. See Branks, 2.
Syn: A check; restrain.