a state in the central United States: a part of the Midwest. 11,418,461; 56,400 sq. mi. (146,075 sq. km). Capital: Springfield. Abbreviation: IL (for use with zip code), Ill.
2.
a river flowing SW from NE Illinois to the Mississippi River: connected by a canal with Lake Michigan. 273 miles (440 km) long.
Pronunciation note The pronunciation of Illinois with a final /z/Show Spelled[z]Show IPA, which occurs chiefly among less educated speakers, is least common in Illinois itself, increasing in frequency as distance from the state increases.
a city in S Massachusetts, on the Connecticut River: the site of the US arsenal and armoury (1794--1968), which developed the Springfield and Garand rifles. Pop: 152 157 (2003 est)
2.
a city in SW Missouri. Pop: 150 867 (2003 est)
3.
a city in central Illinois, capital of the state: the home and burial place of Abraham Lincoln. Pop: 113 586 (2003 est)