Amplified definition of unfamiliar word to things medicine?

Amplified definition of unfamiliar word to things medicine:

Ampulla:

1. A small, sac-like swelling or dilation in a tubular structure, especially the ampulla of Vater which is the dilation at the end of the common bile duct where it joins the pancreatic duct before opening into the duodenum, allowing the controlled release of bile and pancreatic juices into the small intestine for digestion.

2. Refers to the enlargement at one end of a structure; for example, in the semicircular canals of the inner ear or in certain nerve axons such as at the synapses or junctions between nerves.