Source : Webster's Revised Unabridged Dictionary (1913)

Theocracy \The*oc"ra*cy\, n. [Gr. ?; ? God + ? to be strong, to
   rule, fr. ? strength: cf. F. th['e]ocratie. See {Theism}, and
   cf. {Democracy}.]
   1. Government of a state by the immediate direction or
      administration of God; hence, the exercise of political
      authority by priests as representing the Deity.

   2. The state thus governed, as the Hebrew commonwealth before
      it became a kingdom.

Source : WordNet®

theocracy
     n 1: a political unit governed by a deity (or by officials
          thought to be divinely guided)
     2: the belief in government by divine guidance