What is "ampulla of vater"

n. (context anatomy English) A swelling that marks the union of the pancreatic duct and the common bile duct

The ampulla of Vater, also known as the or the hepatopancreatic duct, is formed by the union of the pancreatic duct and the common bile duct. The ampulla is specifically located at the major duodenal papilla.

The ampulla of Vater is an important landmark, halfway along the second part of the duodenum that marks the anatomical transition from foregut to midgut, and hence the point where the celiac trunk stops supplying the gut and the superior mesenteric artery takes over.