leadership is the ability of an individual or a group of people to influence and guide followers or members of an organization, society or team. Leadership often is an attribute tied to a person's title, seniority or ranking in a hierarchy.
Leadership is a social construct; it can only be understood in a social context. When we speak of leadership we usually are thinking of qualities that characterize good leaders - those who are able to create, engage and inspire a team, accomplish goals and develop new leaders. Poor leaders are, in my opinion, characterized by a social disconnection, seeing their skills and their role as sui generis, existing apart from the people in their organization or social sphere.