Source : Webster's Revised Unabridged Dictionary (1913)

Heteronymous \Het`er*on"y*mous\, a. [Hetero- + Gr. "o`nyma, for
   "o`noma a name.]
   Having different names or designations; standing in opposite
   relations. --J. Le Conte. -- {Het"er*on"y*mous*ly}, adv.