ossicle

/ˈɑsɪkəl/
noun
  1. A small bone, especially one of the three tiny bones in the middle ear that help transmit sound.
    • The hammer is one of the three ossicles in the human ear.
    • Birds have a single ossicle in their middle ear, unlike mammals.
    • Doctors examined the ossicles to understand the patient's hearing loss.
  2. Any small bone-like structure in an animal's body.
    • The fossil contained several ossicles from the creature's spine.
    • Biologists studied the ossicles of the ancient fish to learn how it moved.
    • Sea stars have tiny ossicles in their arms that give them structure.