A surgical joining of two hollow structures. It is similar to attaching two ends of a garden hose. For example, a gastrojejunostomy is a surgical procedure that connects the stomach and the jejunum (small intestine.)

When referring to esophageal atresia, it is the surgical joining of the two ends of the esophagus.

The surgical union of two hollow tubular parts (E.G. the ureter and the ileum) to form a passage.