peritoneum /per′itənē″əm/ [Gk, peri + teinein, to stretch] , an extensive serous membrane that lines the entire abdominal wall of the body and is reflected over the contained viscera. It is divided into the parietal peritoneum and the visceral peritoneum. In men the peritoneum is a closed membranous sac. In women it is perforated by the free ends of the uterine tubes. The free surface of the peritoneum is smooth mesothelium, lubricated by serous fluid that permits the viscera to glide easily against the abdominal wall and against one another. The mesentery of the peritoneum fans out from the main membrane to suspend the small intestine. Other parts of the peritoneum are the transverse mesocolon, the greater omentum, and the lesser omentum.
