IllinoianPronunciation: /ˌɪlɪˈnɔɪ(j)ən/Definition of Illinoian adjective Geology relating to or denoting a Pleistocene glaciation in North America, preceding the Wisconsin and approximating to the Saale of northern Europe. (as noun the Illinoian) the Illinoian glaciation or the system of deposits laid down during it. Origin:mid 19th century: from Illinois + -anIllinoian in other Oxford dictionaries Definition of Illinoian in the US English dictionary
