The Collaborative International Dictionary of English v.0.48:

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.
      [1913 Webster]

   2. The state thus governed, as the Hebrew commonwealth before
      it became a kingdom.
      [1913 Webster]

WordNet (r) 3.0 (2006):

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

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "theocracy":
   absolute monarchy, aristocracy, autarchy, autocracy, autonomy,
   coalition government, colonialism, commonwealth,
   constitutional government, constitutional monarchy, democracy,
   dictatorship, dominion rule, duarchy, duumvirate, dyarchy,
   federal government, federation, feudal system, garrison state,
   gerontocracy, heteronomy, hierarchy, hierocracy, home rule,
   limited monarchy, martial law, meritocracy, militarism,
   military government, mob rule, mobocracy, monarchy, neocolonialism,
   ochlocracy, oligarchy, pantisocracy, patriarchate, patriarchy,
   police state, pure democracy, regency, representative democracy,
   representative government, republic, self-determination,
   self-government, social democracy, stratocracy, technocracy,
   thearchy, totalitarian government, totalitarian regime, triarchy,
   triumvirate, tyranny, welfare state



Easton's 1897 Bible Dictionary:

Theocracy
   a word first used by Josephus to denote that the Jews were under
   the direct government of God himself. The nation was in all
   things subject to the will of their invisible King. All the
   people were the servants of Jehovah, who ruled over their public
   and private affairs, communicating to them his will through the
   medium of the prophets. They were the subjects of a heavenly,
   not of an earthly, king. They were Jehovah's own subjects, ruled
   directly by him (comp. 1 Sam. 8:6-9).