Antrum

As antrum - Latin for cave grotto - a bulge or expansion of various structures referred to in the anatomy.

A distinction is made:

Antrum cardiacum, an extension of the esophagus after their passage through the diaphragm and into the stomach before it enters the input
Antral high mori, the old name of the maxillary sinus
Antrum
Pyloric antrum in the entrance segment of the pylorus ( " pylorus " )
Antral ulcer of the stomach