Skip to main content
An official website of the United States government
Español

duodenum

(DOO-ah-DEE-num)
The first part of the small intestine. It connects to the stomach. The duodenum helps to further digest food coming from the stomach. It absorbs nutrients (vitamins, minerals, carbohydrates, fats, proteins) and water from food so they can be used by the body.
Drawing of the small intestine showing the duodenum, jejunum, and ileum. Also shown are the stomach, appendix, large intestine, and rectum.Enlarge this image in new window
The small intestine is a long tube-like organ that connects the stomach to the large intestine. The small intestine includes the duodenum, jejunum, and ileum.
Search NCI's Dictionary of Cancer Terms