Largest hollow space of the body, between the diaphragm and the top of the pelvic cavity and surrounded by the spine and the abdominal muscles and others.
It contains most of the alimentary canal , the liver and pancreas , the spleen , the kidneys , and the adrenal glands . It is lined by the peritoneum, a membrane covering the cavity's inside wall (parietal peritoneum) and each organ or structure in it (visceral peritoneum). Disorders include ascites (fluid in the peritoneal cavity) and peritonitis .