Save Gender Masculine Usage Medieval Scandinavian, Medieval Scottish, Norwegian (Rare) Meaning & History Form of Þórfinnr. Famous bearers include Thorfinn "Skull-splitter", a 10th-century earl of Orkney; Thorfinn Sigurdsson, an 11th-century earl of Orkney; and Thorfinn of Hamar, a 13th-century Norwegian saint.