The esophageal body is the muscular tube part of the esophagus that extends from the upper esophageal sphincter to the lower esophageal sphincter, facilitating the movement of food from the pharynx to the stomach through coordinated peristaltic contractions. It plays a crucial role in the digestive process, and its dysfunction can lead to conditions such as achalasia and gastroesophageal reflux disease (GERD).