Geisel may refer to: Ernesto Geisel (1907–1996), Brazilian military general and politician Orlando Geisel (1905–1979), Brazilian general and Minister of the Army, Ernesto's brother Dr. Seuss, pen name of Theodor Seuss Geisel (1904–1991), a children's book author Theo Geisel (physicist) (born 1948), German physicist Geisel (river), Saxony-Anhalt, Germany Geisel valley, the valley of the river Geisel Geisel Library, the main library building at the University of California San Diego, named after Dr. Seuss See also Geisei, Kōchi, a village in Japan