/dooh'euh dee"neuhm, dyooh'-; dooh od"n euhm, dyooh-/ , n. , pl. duodena /dooh'euh dee"neuh, dyooh'-; dooh od"n euh, dyooh-/ , duodenums . Anat., Zool.
the first portion of the small intestine, from the stomach to the jejunum. See diag. under intestine .
[ 1350-1400; ME intestinum duodenum digitorum intestine of twelve fingerbreadths, with original gen. pl. construed as neut. sing.; L duodeni twelve each (here lacking distributive sense) ]