Pē·ri·ōs'te-ūm, n.

(124), n. [N. Lat., Gr. περιόστεον, from περί, round the bones, from περί, round, and ὀστέον, a bone; It. periosteo, periostio, Sp. periostio, periosto, Fr. périoste.] (Anat.) A fibrous membrane investing the bones. It is necessary to their nutrition, and regenerates osseous substance which has been removed or destroyed.