malleus

Etymology

From Latin malleus (“hammer, mallet”). Doublet of maul.

noun

1. (anatomy) The small hammer-shaped bone of the middle ear.
   A fracture of the malleus handle is a rare traumatic middle ear lesion.
   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 N. Marieb, Katja Hoehn, Human Anatomy & Physiology, 8th edition, page 576
2. (ichthyology) The tripus (ossicle in cypriniform fishes).
3. (zoology) One of the paired calcareous structures within the mastax of rotifers.
   […] in the typical mastax of a Brachionus there are two hammer-like bodies (mallei), which work on a kind of split anvil (incus); […] each malleus consists of an upper part or head (uncus) and a lower or handle (manubrium); 1884, “Memoirs: An Attempt to re-classify the Rotifers”, in Quarterly Journal of Microscopical Science 1884 s2-24, C.T.: Hudson, pages 335-356