what does the term mean?
It is a light frame or ring that holds the foot of a rider, attached to the saddle by a strap.
Stirrup
A stirrup is a light frame or ring that holds the foot of a rider, attached to the saddle by a strap, often called a stirrup leather. 
where is the smallest bone in your body located In the middle ear. does the bone have a name? Yes, stapes or stirrup. what is its function? It transmits sound vibrations from the incus to the oval window. what does the window mentioned above refer to? It is a membrane-covered opening from the middle ear to the cochlea of the inner ear. how did the smallest bone get its other name? Because of its resemblance to a stirrup.
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Stirrup [SEP] Introduction
A stirrup is a light frame or ring that holds the foot of a rider, attached to the saddle by a strap, often called a stirrup leather. Stirrups are usually paired and are used to aid in mounting and as a support while using a riding animal (usually a horse or other equine, such as a mule). They greatly increase the rider's ability to stay in the saddle and control the mount, increasing the animal's usefulness to humans in areas such as communication, transportation and warfare. In antiquity, the earliest foot supports (appearing in India by the 2nd century BC) consisted of riders placing their feet under a girth or using a simple toe loop.