Definition of ossicle in US English:



Anatomy Zoology
  • 1A very small bone, especially one of those in the middle ear.

    • ‘Internally, the mastoid is hollowed out to form the epitympanic recess to accommodate the ossicles of the middle ear.’
    • ‘Sutural bones are usually small, irregularly shaped ossicles, often found in the sutures of the cranium, especially in the parietal bones.’
    • ‘The middle ear ossicles and tympanic membrane remained intact, so sound stimulation could be applied to the preparation through a loudspeaker connected to the external ear canal.’
    • ‘Sound waves reaching the tympanic membrane will initiate vibrations that are transmitted through the bony ossicles of the middle ear to the oval window.’
    • ‘Vibrations of the eardrum are then coupled by the middle ear ossicles, the three smallest bones in the body, to the fluid-filled cochlea.’
    1. 1.1 A small piece of calcified material forming part of the skeleton of an invertebrate animal such as an echinoderm.
      • ‘Most such particles are echinoderm stem ossicles, brachiopods, bryozoans or other corals.’
      • ‘The position of these plates on the non-rudiment side of the larva suggests that ossicles occurring on the aboral surface are extraxial.’
      • ‘As they grow, asteroids add new ossicles and increase size of existing ossicles.’
      • ‘Calcareous ossicles make up the internal skeleton.’
      • ‘The calcitic ossicles of crinoids, as is typical of echinoderms, form an internal skeleton that provides support and protection.’


Late 16th century: from Latin ossiculum, diminutive of os ‘bone’.