parietal bone

parietal bone   n.  Either of two large, irregularly quadrilateral bones between the frontal and occipital bones that together form the sides and top of the skull.

Main Entry: parietal bone
Function: noun
: either of a pair of membrane bones of the roof of the skull between the frontal and occipital bones that are large andquadrilateral in outline, meet in the sagittal suture, and form much of the top and sides of the cranium

parietal bone n.
Either of two irregularly quadrilateral bones between the frontal and occipital bones that together form the sides and top of the skull.

parietal bone

cranial bone forming part of the side and top of the head. In front each parietal bone adjoins the frontal bone; in back, the occipital bone; and below, the temporal and sphenoid bones. The parietal bones are marked internally by meningeal blood vessels and externally by the temporal muscles. They meet at the top of the head (sagittal suture) and form a roof for the cranium. The parietal bone forms in membrane (i.e., without a cartilaginous precursor); the sagittal suture closes between ages 22 and 31. In primates that have large jaws and well-developed chewing muscles (e.g., gorillas and baboons), the parietal bones may be continued upward at the midline to form a sagittal crest. Among early hominids, Paranthropus (also called Australopithecus robustus) sometimes exhibited a sagittal crest.

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