stapes

Etymology

From Medieval Latin stapēs (“stirrup”). Doublet of step.

noun

1. (anatomy, zootomy) A small stirrup-shaped innermost ossicle of the middle ear of mammals, transmitting vibrations from the incus to the inner ear.
   The tympanic cavity is spanned by the three smallest bones in the body: the auditory ossicles[…] These bones, named for their shape, are the malleus (malʹe-us; "hammer"); the incus (ingʹkus; "anvil"); and the stapes (staʹpēz; "stirrup"). The "handle" of the malleus is secured to the eardrum, and the base of the stapes fits into the oval window. 2010, Elaine Nicpon Marieb, Katja Hoehn, Human Anatomy & Physiology, 8th edition, page 576