noun (n)

• dominance or power through legal authority(noun.state)

  Example:
  France held undisputed dominion over vast areas of Africa.
  

  Synonym:
  rule
  

  source: wordnet30
• a region marked off for administrative or other purposes(noun.location)

  Synonym:
  district, territorial dominion, territory
  

  source: wordnet30
• one of the self-governing nations in the British Commonwealth(noun.group)

  source: wordnet30
• Sovereign or supreme authority; the power of governing and controlling; independent right of possession, use, and control; sovereignty; supremacy.(noun)

  source: webster1913