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a peritoneal depression on either side of the rectum formed by peritoneal (sacrogenital) folds passing from the posterolateral pelvic wall to the central pelvic viscera. The fossa is a lateral extension of the male rectovesical pouch or the female rectouterine pouch.
either of two cavities formed by folds of the peritoneum, one on either side of the rectum, varying in size according to distension of the rectum. In males this is continuous with the rectovesical pouch, and in females it is continuous with the rectouterine pouch.