A group or association of cooperating members.

“the League of Nations”

An organization of sports teams which play against one another for a championship.

“My favorite sports organizations are the National Football League and the American League in baseball.”

(often in the negative) A class or type of people or things that are evenly matched or on the same level.

“Forget about dating him; he's out of your league.”

To form an association; to unite in a league or confederacy; to combine for mutual support.

A version of rugby football, played between two teams of thirteen.