diaphragm

(di’af-ram) [Gr. 514 acro + φράγμα wall]. 1. The musculomembranous partition that separates the abdomen from the thorax. 2. Any thin septum. 3. A disk with one or more openings in it mounted in front of a lens to shut off part of the light from it. pelvic d., diaphragm a pelvis. urogenital d., the triangular ligament of the perineum.