Illinois is defined as a member of the group of Native Americans who lived in North Illinois, South Wisconsin and parts of Missouri and Iowa or the language of these people, or a midwestern state in the United States and a 273 mile river that flows through this state into the Mississippi River.(noun)
See Illinois in Webster's New World College Dictionary
Origin: Fr, earlier also Ilinoués < name in an unidentified Algonquian language: perhaps orig. meaning ordinary speaker
See Illinois in American Heritage Dictionary 4
noun pl. Illinois Illinois
Origin: French, of Algonquian origin.
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