Source : Webster's Revised Unabridged Dictionary (1913)

Ownership \Own"er*ship\, n.
   The state of being an owner; the right to own; exclusive
   right of possession; legal or just claim or title;
   proprietorship.

Source : WordNet®

ownership
     n 1: the relation of an owner to the thing possessed; possession
          with the right to transfer possession to others
     2: the act of having and controlling property [syn: {possession}]
     3: the state or fact of being an owner