deep fascia, the most extensive of three kinds of fascia comprising an intricate series of connective sheets and bands that hold the muscles and other structures in place throughout the body, wrapping the muscles in gray, feltlike membranes. The deep fasciae comprise a continuous system, splitting and fusing in an elaborate network attached to the skeleton and divided into the outer investing layer, the internal investing layer, and the intermediate membranes. Compare subcutaneous fascia, subserous fascia.
