suboesophageal

from The Collaborative International Dictionary of English v.0.48

Subesophageal \Sub*e`so*phag"e*al\, a. (Zool.)
   Situated beneath the esophagus. [Written also
   {suboesophageal}.]
   [1913 Webster]

   {Subesophageal ganglion} (Zool.), a large special ganglion
      situated beneath the esophagus of arthropods, annelids,
      and some other invertebrates.
      [1913 Webster]