Chicago Syllabification: (Chi·ca·go)Pronunciation: /SHiˈkôgō, -ˈkägō/Definition of Chicago a city in northeastern Illinois, on Lake Michigan; population 2,853,114 (est. 2008). Chicago developed during the 19th century as a major grain market and food-processing center. Derivatives ChicagoanPronunciation: /-ˈkôgō-ən, -ˈkäg-/ noun & adjective Chicago in other Oxford dictionaries Definition of Chicago in the British & World English dictionary