Frank Fitch Grout (January 24, 1880, Rockford, Illinois – August 1, 1958, Minneapolis) was an American petrographer, geologist, and mineralogist.[1] He is perhaps best known for introducing the term lopolith into the science of geology.[2] The mineral groutite is named in Grout's honor (based upon a 1945 discovery by John Walter Gruner).[3]