That portion of the body that lies between the THORAX and the PELVIS.

The region in the abdomen extending from the thoracic DIAPHRAGM to the plane of the superior pelvic aperture (pelvic inlet). The abdominal cavity contains the PERITONEUM and abdominal VISCERA, as well as the extraperitoneal space which includes the RETROPERITONEAL SPACE.

An area occupying the most posterior aspect of the ABDOMINAL CAVITY. It is bounded laterally by the borders of the quadratus lumborum muscles and extends from the DIAPHRAGM to the brim of the true PELVIS, where it continues as the pelvic extraperitoneal space.

A membrane of squamous EPITHELIAL CELLS, the mesothelial cells, covered by apical MICROVILLI that allow rapid absorption of fluid and particles in the PERITONEAL CAVITY. The peritoneum is divided into parietal and visceral components. The parietal peritoneum covers the inside of the ABDOMINAL WALL. The visceral peritoneum covers the intraperitoneal organs. The double-layered peritoneum forms the MESENTERY that suspends these organs from the abdominal wall.

A double-layered fold of peritoneum that attaches the STOMACH to other organs in the ABDOMINAL CAVITY.

The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.

A layer of the peritoneum which attaches the abdominal viscera to the ABDOMINAL WALL and conveys their blood vessels and nerves.

The fold of peritoneum by which the COLON is attached to the posterior ABDOMINAL WALL.

The outer margins of the ABDOMEN, extending from the osteocartilaginous thoracic cage to the PELVIS. Though its major part is muscular, the abdominal wall consists of at least seven layers Abdominal Muscles;

The external junctural region between the lower part of the abdomen and the thigh.

The tunnel in the lower anterior ABDOMINAL WALL through which the SPERMATIC CORD, in the male; ROUND LIGAMENT, in the female; nerves; and vessels pass. Its internal end is at the deep inguinal ring and its external end is at the superficial inguinal ring.

The pit in the center of the ABDOMINAL WALL marking the point where the UMBILICAL CORD entered in the FETUS. OMPHALO- (navel)