Reins, n. pl.
(rānz), n. pl. [Fr. rein, pl. reins, O. Fr. rain, Pr. ren, re, O. Sp. ren, rene, N. Sp. riñon, equiv. to Fr. rognon, It. ornione, argnone, Pg. rins, It. rene, Lat. ren, pl. renes.]
Sense 1. The kidneys.
Sense 2. The lower part of the back, being the ribs and hip-bone, over the kidneys.
Sense 3. Hence, the inward impulses; the affections and passions; — so called because formerly supposed to have their seat in that part of the body.
My reins shall rejoice when thy lips speak right things. Prov. xxiii. 16.
I am he which searcheth the reins and hearts. Rev. ii. 23.
Reins of a vault (Arch.), the sides or walls that sustain the arch. Gecil. — To give the reins, to give license; to allow to be without restraint. — To take the reins, to assume control.