Emily Dickinson Lexicon

STIR-RUP, n. [stur'up; Sax. stige-rapa, step-rope; stigan, to step or ascend, and rap, rope; G. steig-bugel, step-bow or mounting-bow; D. styg-beugel; Sw. steg-bögel; Dan. stig-böjle. The first stirrups appear to have been ropes.]

A kind of ring or bending piece of metal, horizontal on one side for receiving the foot of the rider, and attached to a strap which is fastened to the saddle; used to assist persons in mounting a horse, and to enable them to sit steadily in riding, as well as to relieve them by supporting a part of the weight of the body.