du·o·de·num (d′ə-dēnəm, dy′-, d-ŏdn-əm, dy-)
n. pl. du·o·de·na (d′ə-dēnə, dy′-, d-ŏdn-ə, dy-) or du·o·de·nums
The beginning portion of the small intestine, starting at the lower end of the stomach and extending to the jejunum.
[Middle English, from Medieval Latin, short for intestīnum duodēnum digitōrum, intestine of twelve finger-widths (in length), from Latin duodēnum, genitive pl. of duodēnī, twelve each, from duodecim, twelve; see DUODECIMAL.]
du′o·denal (d′ə-dēnəl, dy′-, d-ŏdn-əl, dy-) adj.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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