William G. Edens was a Chicago banker and an early-20th Century proponent of the modern road and highway system. As president of the Illinois Highway Improvement Association, he played a major role in promoting the state's first $60 million state highway bond issue in 1918, which passed. He was present for the opening of the first segment of the expressway that was named for him (at the time, designated IL-194) in 1951, and according to one account, could not drive nor owned a car.
The Gaper's Block link is a dictionary of terms you'll hear on Chicago radio traffic reports ("Inbound Edens, 19 minutes Lake Cook to the Junction...") This isn't the first time I've tried to find this out, but the last time, Google searches didn't turn up anything useful, and the Wikipedia entry was pretty empty. It's all fixed now. Also useful: This guide to expressway interchange types.