rein

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A long narrow leather strap attached to each end of the bit of a bridle and used by a rider or driver to control a horse or other animal. Often used in the plural.
2. n. A means of restraint, check, or guidance.
3. n. A means or an instrument by which power is exercised. Often used in the plural: the reins of government.
4. v. To check or hold back by or as if by the use of reins. Often with in, back, or up.
5. v. To restrain or control.
6. v. To control a horse, for example, with reins.
7. idiom. draw in the reins To slow down or stop by or as if by pressure on the reins.
8. idiom. free To release from restraints; allow to go unchecked: gave rein to her emotions.
9. idiom. tight rein Close control: kept expenses on a tight rein.

Century Dictionary and Cyclopedia

1. n. The strap of a bridle, fastened to the curb or snaffle on each side, by which the rider or driver restrains and guides the animal driven; any thong or cord used for the same purpose. See cut under harness.
2. n. A rope of twisted and greased rawhide.
3. n. plural The handles of blacksmiths' tongs, on which the ring or coupler slides.
4. n. Figuratively, any means of curbing, restraining, or governing; government; restraint.
5. To govern, guide, or restrain by reins or a bridle.
6. To restrain; control.
7. To carry stiffly, as a horse does its head or neck under a bearing-rein.
8. To obey the reins.
9. n. An obsolete singular of reins.

Wiktionary

1. n. A strap or rope attached to the bridle or bit, used to control a horse, animal or young child.
2. v. To direct or stop a horse by using reins.
3. v. this sense?) (usually "rein in") To stop or restrain a horse. Also used figuratively
4. n. archaic, chiefly in plural A kidney.

GNU Webster's 1913

1. n. The strap of a bridle, fastened to the curb or snaffle on each side, by which the rider or driver governs the horse.
2. n. Hence, an instrument or means of curbing, restraining, or governing; government; restraint.
3. v. To govern or direct with the reins.
4. v. To restrain; to control; to check.
5. v. rare To be guided by reins.

WordNet 3.0

1. n. one of a pair of long straps (usually connected to the bit or the headpiece) used to control a horse
2. v. control and direct with or as if by reins
3. n. any means of control
4. v. keep in check
5. v. stop or check by or as if by a pull at the reins
6. v. stop or slow up one's horse or oneself by or as if by pulling the reins