Source : Webster's Revised Unabridged Dictionary (1913)

Homophonic \Ho`mo*phon"ic\, Homophonous \Ho*moph"o*nous\, a.
   [Gr. ?; ? the same + ? sound, tone: cf. F. homophone.]
   1. (Mus.)
      (a) Originally, sounding alike; of the same pitch;
          unisonous; monodic.
      (b) Now used for plain harmony, note against note, as
          opposed to polyphonic harmony, in which the several
          parts move independently, each with its own melody.

   2. Expressing the same sound by a different combination of
      letters; as, bay and bey.

Source : WordNet®

homophonous
     adj : the phenomenon of words of different origins coming to
           pronounced the same way; "homophonous words"