Esophagogastroduodenoscopy
Esophagogastroduodenoscopy: Also known as EGD or upper endoscopy.
A procedure that enables the examiner (usually a gastroenterologist) to examine the esophagus (the swallowing tube), stomach, and duodenum (the first portion of small bowel) using a thin flexible tube (a 'scope') that can be looked through or seen on a TV monitor.
(A great crossword puzzle/trivia term!