1. The kidneys; also, the region of the kidneys; the loins. 2. The inward impulses; the affections and passions; -- so called because formerly supposed to have their seat in the part of the body where the kidneys are. My reins 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 parts betw...
