The Collaborative International Dictionary of English v.0.48:

Antipode \An"ti*pode\, n.
   One of the antipodes; anything exactly opposite.
   [1913 Webster]

         In tale or history your beggar is ever the just
         antipode to your king.                   --Lamb.
   [1913 Webster]

   Note: The singular, antipode, is exceptional in formation,
         but has been used by good writers. Its regular English
         plural would be [a^]n"t[i^]*p[=o]des, the last syllable
         rhyming with abodes, and this pronunciation is
         sometimes heard. The plural form (originally a Latin
         word without a singular) is in common use, and is
         pronounced, after the English method of Latin,
         [a^]n*t[i^]p"[-o]*d[=e]z.
         [1913 Webster]

WordNet (r) 3.0 (2006):

antipode
    n 1: direct opposite; "quiet: an antipode to focused busyness"