archenteron

from WordNet (r) 3.0 (2006)

archenteron
    n 1: central cavity of the gastrula; becomes the intestinal or
         digestive cavity

from The Collaborative International Dictionary of English v.0.48

Archenteron \Arch`en"ter*on\, n. [Pref. arch- + Gr. ?
   intestine.] (Biol.)
   The primitive enteron or undifferentiated digestive sac of a
   gastrula or other embryo. See Illust. under {Invagination}.
   [1913 Webster]