mastoid process n.
A conical protuberance of the posterior portion of the temporal bone that is situated behind the ear and serves as a site of muscle attachment. Also called mastoid bone.
The part of the first pharyngeal arch in the embryo, developing into the upper jaw in the embryo.
|mastoid process (mās'toid') Pronunciation Key
A protruding bony area in the lower part of the skull that is located behind the ear in humans and many other vertebrates and serves as a site of muscle attachment. The mastoid process contains small air-filled cavities called mastoid cells that communicate with the middle ear.
the smooth pyramidal or cone-shaped bone projection at the base of the skull on each side of the head just below and behind the ear in humans. The mastoid process is important to students of fossil humans because it occurs regularly and in the specific form described only in hominids (i.e., members of the genera Homo and Australopithecus). The development of the mastoid process is apparently related to the upright posture of hominids and the consequent evolutionary realignment of the head in relation to the neck
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