Pronunciation: (per"ē-os'tē-um), [key]
—pl. -te•aPronunciation: (-tē-u). [key] Anat.
the normal investment of bone, consisting of a dense, fibrous outer layer, to which muscles attach, and a more delicate, inner layer capable of forming bone.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.