The Collaborative International Dictionary of English v.0.48:

oenanthylic \oe`nan*thyl"ic\, a. (Chem.)
   Pertaining to, derived from, or containing, oenanthyl;
   specifically, designating an acid formerly supposed to be
   identical with the acid in oenanthic ether, but now known to
   be identical with heptanoic acid.

   Note: Oenanthylic and oenanthic are now considered as
         syonyms (1999).
         [1913 Webster +PJC]