Merriam-Webster's Collegiate® Dictionary, 11th Edition
LEAGUE
I. noun
Etymology: Middle English leuge, lege, from Late Latin leuga
Date: 14th century
any of various units of distance from about 2.4 to 4.6 statute miles (3.9 to 7.4 kilometers), a square league,
II. noun see: ligature
Date: 15th century
1. an association of nations or other political entities for a common purpose, b. an association of persons or groups united by common interests or goals, a group of sports teams that regularly play one another, an informal alliance , class , category ,
III. verb (leagued; leaguing)
Date: 1604
transitive verb to unite in a league, intransitive verb to form a league