[ il-uh-noi or, sometimes, -noiz ]

noun,plural Il·li·nois [il-uh-noi, -noiz]. /ˌɪl əˈnɔɪ, -ˈnɔɪz/.
  1. a member of a confederacy of North American Indians of Algonquian stock, formerly occupying Illinois and adjoining regions westward.

  2. the Algonquian language of the Illinois and Miami Indians.

Origin of Illinois

1715–25, Americanism;<French, earlier Eriniouai, Ilinoués, etc., from an unidentified Algonquian language, apparently literally, “one who sounds normal” (i.e., “a person who speaks an Algonquian language”), equivalent to the (unattested) Proto-Algonquian elements elen- “ordinary” + -we “make sound”

Words Nearby Illinois

Other definitions for Illinois (2 of 2)

[ il-uh-noi or, sometimes, -noiz ]

  1. a state in the central United States: a part of the Midwest. 56,400 sq. mi. (146,075 sq. km). Capital: Springfield. Abbreviations: IL (for use with zip code), Ill.

  2. a river flowing southwest from northeastern Illinois to the Mississippi River: connected by a canal with Lake Michigan. 273 miles (440 km) long.

pronunciation note For Illinois

The pronunciation of Illinois with a final [z], /z/, which occurs chiefly among less educated speakers, is least common in Illinois itself, increasing in frequency as distance from the state increases. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use Illinois in a sentence

British Dictionary definitions for Illinois


/ (ˌɪlɪˈnɔɪ) /

  1. a state of the N central US, in the Midwest: consists of level prairie crossed by the Illinois and Kaskaskia Rivers; mainly agricultural. Capital: Springfield. Pop: 12 653 544 (2003 est). Area: 144 858 sq km (55 930 sq miles): Abbreviation: Ill., (with zip code) IL

  2. a river in Illinois, flowing SW to the Mississippi. Length: 439 km (273 miles)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for Illinois


[ (il-uh-noy) ]

State in the north-central United States bordered on the north by Wisconsin, the east by Indiana, the south by Kentucky, and the west by Missouri and Iowa. Its capital is Springfield, and its largest city is Chicago.

Notes for Illinois

Known as the “Land of Lincoln” because Abraham Lincoln began his political career there.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.