What does "bridle" mean?

Additional senses

1. 2.(Gun.) The piece in the interior of a gun lock, which holds in place the timbler, sear, etc.
2. 3.(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. 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.
3. 4.To put a bridle upon; to equip with a bridle; as, to bridle a horse. He bridled her mouth with a silkweed twist. Drake.
4. 5.To restrain, guide, or govern, with, or as with, a bridle; to check, curb, or control; as, to bridle the passions; to bridle a muse. Addison. Savoy and Nice, the keys of Italy, and the citadel in her hands to bridle Switzerland, are in that consolidation. Burke.
5. 6.To hold up the head, and draw in the chin, as an expression of pride, scorn, or resentment; to assume a lofty manner; -- usually with up. "His bridling neck." Wordsworth. By her bridling up I perceived she expected to be treated hereafter not as Jenny Distaff, but Mrs. Tranquillus. Tatler.