Merriam-Webster Collegiate Dictionary - stirrup

 noun  Etymology: Middle English stirop, from Old English stigrap, from stig- (akin to Old High German stigan to go up) + rap rope — more at stair, rope  Date: before 12th century  1. either of a pair of small light frames or rings for receiving the foot of a rider that are attached by a strap to a saddle and used to aid in mounting and as a support while riding  2. a piece resembling a ~: as  a. one used as a support or clamp in carpentry and machinery  b. a ~-shaped footrest  3. a rope secured to a yard and attached to a thimble in its lower end for supporting a footrope  4. stapes