The esophagus (American English) or oesophagus (British English; see spelling differences) (/ɪˈsɒfəɡəs/), commonly known as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about 25 centimeters (10 in) long in adults, which travels behind the trachea and heart, passes through the diaphragm and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word oesophagus is the Greek word οἰσοφάγος oisophagos, meaning "gullet".

The esophagus is one of the upper parts of the digestive system. There are taste buds on its upper part. It begins at the back of the mouth, passing downwards through the rear part of the mediastinum, through the diaphragm, and into the stomach. In humans, the esophagus generally starts around the level of the sixth cervical vertebra behind the cricoid cartilage of the trachea, enters the diaphragm at about the level of the tenth thoracic vertebra, and ends at the cardia of the stomach, at the level of the eleventh thoracic vertebra.

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