Chi·ca·go (sh?-kä?g?, -kô?-) The largest city of Illinois, in the northeast part of the state on Lake Michigan. Located at the mouth of the Chicago River, the first link in the Illinois Waterway, it developed into a major port in the 1800s and became the commercial center of the Midwest. Chicago was nearly destroyed by a disastrous fire in 1871.Chi·ca?go·an n.Word History: The name Chicago is first recorded in 1688 in a French document, where it appears as Chigagou, an Algonquian word meaning “onion field.” In explanation of this name, the document states that wild onion or garlic grew profusely in the area. The name of the field or meadow was first transferred to the river and then was given to the city in 1830.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.Chicago (???k?????) n (Placename) a port in NE Illinois, on Lake Michigan: the third largest city in the US; it is a major railway and air traffic centre. Pop: 2 869 121 (2003 est)Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014Chi?ca?go (???k? go?, -?k?-) n. a city in NE Illinois, on Lake Michigan: third largest city in the U.S. 2,721,547 Chi?ca?go?an, n. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.