• (n.) The periosteum which covers the cranium externally; the region around the cranium.
(per″e-kra´ne-әm) the periosteum of the skull. adj., pericra´nial., adj.
Per`i·cra'ni·um noun [ New Latin ] (Anat.) The periosteum which covers the cranium externally; the region around the cranium. 
Type: Term Pronunciation: per′i-krā′nē-ŭm Definitions: 1. The periosteum of the skull. Synonyms: periosteum cranii
pericranium (s), pericrania (pl) The membrane of connective tissue that surrounds the skull.
Greek peri = around, and kranion = skull; hence, the external periosteum of the skull.