What is the shape of the stomach?

The stomach is shaped like a J. When empty, the human stomach is a muscular, expandable sac that is roughly J-shaped, but when filled with food, it can expand to several times its original size. 

The top of the J-shape is the fundus, which is the upper, rounded portion of the stomach near the esophageal entrance. 

The main part of the stomach is the body, which is where the majority of the food is mixed and churned by the muscular contractions of the stomach wall. 

The pylorus, which is the narrow, lower portion of the stomach that leads to the small intestine, is located at the bottom of the J-shape.

The pylorus regulates the passage of partially digested food into the small intestine, where it is further digested and absorbed.