Stirrup

light frame or ring that holds the foot of a rider

The stirrup is a ring with a flat bottom fixed on a leather strap, usually hung from each side of a saddle to create a footrest for the rider on a riding animal (usually a horse or a mule), suspended by an adjustable strap from the saddle for use as a support for the foot of a rider of a horse when seated in the saddle and as an aid in getting up.

Stirrup