'Duodenum' definitions:

Definition of 'duodenum'

(from WordNet)
noun
The part of the small intestine between the stomach and the jejunum

Definition of 'Duodenum'

From: GCIDE
  • Duodenum \Du`o*de"num\, n. [NL., fr. duodeni twelve each: cf. F. duodenum. So called because its length is about twelve fingers' breadth.] (Anat.) The part of the small intestines between the stomach and the jejunum. See Illust. of Digestive apparatus, under Digestive. [1913 Webster]