The Collaborative International Dictionary of English v.0.48:

Epipharyngeal \Ep`i*phar`yn*ge"al\, a. [Pref. epi- +
   pharyngeal.] (Anat.)
   Pertaining to the segments above the epibranchial in the
   branchial arches of fishes. -- n. An epipharyngeal bone or
   cartilage.
   [1913 Webster]