Emily Dickinson Lexicon

PER-I-OS'TE-UM, n. [Gr. περι, about, and οστεον, bone.]

A nervous vascular membrane endued with quick sensibility, immediately investing the bones of animals. – Encyc. Coxe. The periosteum has very little sensibility in a sound state, but in some cases of disease it appears to be very sensible. – Wistar.