- a member of the Algonquian people formerly of Illinois and regions to the west
- A state in the eastern central US; pop. 12,419,293; capital, Springfield; statehood, Dec. 3, 1818 (21). Colonized by the French in the 1600s and ceded to Britain in 1763, it was acquired by the US in 1783
- a midwestern state in north-central United States
- Illinois ( ), is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country.