Malleus
From Memory Alpha, the free Star Trek reference.
The malleus is a hammer-shaped small bone inside the ear, which connects with the incus and is attached to the inner surface of the eardrum.
In 2371, Kes was studying medical texts to become a nurse on board the USS Voyager. The Doctor tested Kes on the various parts of the ear, including malleus. (VOY: "Eye of the Needle")
