Rein (r?n), n. [F. rêne, fr. (assumed) LL. retina, fr. L. retinere to hold back. See Retain.] 1. The strap of a bridle, fastened to the curb or snaffle on each side, by which the rider or driver governs the horse.
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This knight laid hold upon his reyne. Chaucer.
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2. Hence, an instrument or means of curbing, restraining, or governing; government; restraint. “Let their eyes rove without rein.” Milton.
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To give rein, To give the rein to, to give license to; to leave withouut restrain. -- To take the reins, to take the guidance or government; to assume control.
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Rein, v. i. To be guided by reins. [R.] Shak.
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