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a division of a larger structure.
mastoid part of temporal bone the posterior portion of the petrous (or petromastoid) part. Called also mastoid bone.
petromastoid part of temporal bone see petrous part of temporal bone.
petrous part of temporal bone the part of the temporal bone located at the base of the cranium, containing the inner ear. Some anatomists divide it into two separate subparts, calling the posterior section the mastoid part, reserving the term petrous part for the anterior section only, and calling the entire area the petromastoid part. Called also petrous bone.
squamous part of temporal bone the flat, scalelike, anterior superior portion of the temporal bone. Called also squamous bone.
Relating to the parietal bone and the squamous portion of the temporal bone.