Source : Webster's Revised Unabridged Dictionary (1913)

Leadership \Lead"er*ship\, n.
   The office of a leader.

Source : WordNet®

leadership
     n 1: the activity of leading; "his leadership inspired the team"
          [syn: {leading}]
     2: the body of people who lead a group; "the national
        leadership adopted his plan" [syn: {leaders}]
     3: the status of a leader; "they challenged his leadership of
        the union"
     4: the ability to lead; "he believed that leadership can be
        taught"