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Sāturnīnus, i, m., a Roman surname. So esp. L. Appuleius Saturninus, a tribune of the people A.U.C. 654; who, with C. Servilius Glaucia, was pronounced guilty of treason and put to death, Cic. Rab. Perd. 6, 18; id. Brut. 62, 224; id. Cat. 1, 2, 4; id. Mil. 5, 14; Suet. Aug. 27; id. Calig. 38; Mart. 4, 11, 2.