the GNU version of the Collaborative International Dictionary of English
n. The membrane of fibrous connective tissue which closely invests all bones except at the articular surfaces.
The Century Dictionary and Cyclopedia
n. The enveloping membrane of bones; a dense fibrous membrane firmly investing the surface of bones, except where they are covered by cartilage.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles; contains nerves and blood vessels that nourish the enclosed bone
Word Usage
"The shaft is covered by a membrane called the periosteum and is what the muscles attach to."