Source : Webster's Revised Unabridged Dictionary (1913)

Binaural \Bin*au"ral\, a. [Pref. bin- + aural.]
   Of or pertaining to, or used by, both ears.

Source : WordNet®

binaural
     adj : relating to or having or hearing with two ears; "binaural
           hearing" [syn: {biaural}] [ant: {monaural}]