ossicle

Etymology

Late 16th century, from Latin ossiculum (“little bone, ossicle”) from os (“bone”).

noun

1. (anatomy) A small bone (or bony structure), especially one of the three of the middle ear.
   The incus is one of the three auditory ossicles.
2. (zoology) Bone-like joint or plate, especially:
   1. one of numerous small calcareous structures forming the skeleton of certain echinoderms, as the starfishes;
   2. one of the hard articuli or joints of the stem or branches of a crinoid or encrinite;
   3. one of the several small hard chitinous parts or processes of the gastric skeleton of crustaceans, as in the stomach of a lobster or crawfish.