An association of states, organizations, or individuals for common action; an alliance. Sports An association of teams or clubs that compete chiefly among themselves. Also called loop1. A class or level of competition: The ski jump was out of his league. To come together in or as if in a league. To bring together in or as if in a league. A unit of distance equal to 3.0 statute miles (4.8 kilometers). Any of various other units of about the same length. A square league.