The Collaborative International Dictionary of English v.0.48:
Gastroduodenal \Gas`tro*du"o*de"nal\, a. [Gastro- + -duodenal.] (Anat.) Pertaining to the stomach and duodenum; as, the gastroduodenal artery. [1913 Webster]WordNet (r) 3.0 (2006):
gastroduodenal adj 1: of or relating to the stomach and the duodenum