duodenum

noun

Etymology: From Medieval Latin duodēnum digitōrum (“space of twelve digits”) in reference to its length, from duodēnī (“twelve each”) + digitōrum, genitive plural of digitus (“finger; toe; digit”).

1. The first part of the small intestine, starting at the lower end of the stomach and extending to the jejunum.

   “From the Stomacke to the very Fundament, are produced the Guts or Inteſtina, which ſerue a little to alter and diſtribute the Chilus, and convey away the excrements. They are divided into ſmall and great, by reason of their ſite and ſubſtance, ſlender or thicker. The ſlender is Duodenum or whole gut, which is next to the ſtomacke, ſome twelue inches long (ſaith Fuſchius.)”

   “The Inteſtina tenuia were burnt in many places, but not quite through any where, excepting two or three. […] The length of that which is commonly call'd the Duodenum, was about 4½ Foot.”