Abdomen

Abdomen
The human abdomen and organs which can be found beneath the surface
Details
Actions	Movement and support for the torso Assistance with breathing Protection for the inner organs Postural support
Identifiers
Latin	abdomen
Greek	ἦτρον
MeSH	D000005
TA98	A01.1.00.016
TA2	127
FMA	9577
Anatomical terminology [edit on Wikidata]

The abdomen (colloquially called the belly, tummy, midriff, tucky, or stomach^{[citation needed]}) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior tagma of the body; it follows the thorax or cephalothorax.^[1]

In humans, the abdomen stretches from the thorax at the thoracic diaphragm to the pelvis at the pelvic brim. The pelvic brim stretches from the lumbosacral joint (the intervertebral disc between L5 and S1) to the pubic symphysis and is the edge of the pelvic inlet. The space above this inlet and under the thoracic diaphragm is termed the abdominal cavity. The boundary of the abdominal cavity is the abdominal wall in the front and the peritoneal surface at the rear.

In vertebrates, the abdomen is a large body cavity enclosed by the abdominal muscles, at the front and to the sides, and by part of the vertebral column at the back. Lower ribs can also enclose ventral and lateral walls. The abdominal cavity is continuous with, and above, the pelvic cavity. It is attached to the thoracic cavity by the diaphragm. Structures such as the aorta, inferior vena cava and esophagus pass through the diaphragm. Both the abdominal and pelvic cavities are lined by a serous membrane known as the parietal peritoneum. This membrane is continuous with the visceral peritoneum lining the organs.^[2] The abdomen in vertebrates contains a number of organs belonging to, for instance, the digestive system, urinary system, and muscular system.