Definition of foreguts:
(n) :
(biology, anatomy, medicine) The developed counterpart in the adult: the proximal part of the alimentary canal, which in humans runs from the mouth to the first half of the duodenum, up to the ampulla of Vater.
(n) :
(biology, anatomy, embryology) The anterior part of the alimentary canal of an embryo, from the mouth to the duodenum, in humans and some other animals.