William Madison Furnish (born August 17, 1912, in Tipton, Iowa, died November 9, 2007) was an American paleontologist. He taught at the University of Iowa. In 1938, he described the conodont genus Acanthodus from the Prairie du Chien (Lower Ordovician) beds of the upper Mississippi valley. In 1964, with , he described the conodont genus Hindeodus from the Pella Formation (Mississippian) of South-Central Iowa.