The Collaborative International Dictionary of English v.0.48:

Macedon \Macedon\, Macedonia \Macedonia\prop. n.
   the ancient kingdom of Phillip II and Alexander the Great in
   the Southeastern Balkans that is now part of Greece, Bulgaria
   and the former Yugoslavia.

   Syn: Macedonia.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Macedon
    n 1: the ancient kingdom of Philip II and Alexander the Great in
         the southeastern Balkans that is now divided among modern
         Macedonia and Greece and Bulgaria [syn: Macedon,
         Macedonia, Makedonija]