Duodenum

n. part of the small intestine

In anatomy of the digestive system, the duodenum is a hollow jointed tube about 25-30 cm long connecting the stomach to the jejunum. It is the first and shortest part of the small intestine and it is where most chemical digestion takes place. It begins with the duodenal bulb and ends at the ligament of Treitz. The name duodenum is from the Latin duodenum digitorum, twelve fingers' breadths.
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Duodenum /du·o·de·num/ the first or proximal portion of the small intestine, extending from the pylorus to the jejunum.duode´nal du·o·de·num n. pl. [more]Duodenum - Community and Resources

Noun
1. the part of the small intestine between the stomach and the jejunum
(hypernym) small intestine

n. duodenum, part of the small intestine