Elgin (ĕlˈjĭn) [key], city (1990 pop. 77,010), Cook and Kane counties, NE Ill., on the Fox River; inc. 1854. Elgin is a railroad, trade, and industrial city marked by a steady population growth. Corn and soybeans are grown and electrical and electronic equipment, pharmaceuticals, and household appliances are manufactured. The Elgin Watch Company (est. 1864) was based in the city until 1970. Judson College is there.