A surname of Apollo at Rome, where Augustus, in commemoration of the battle of Actium, dedicated a temple to the god on the Palatine hill, in which subsequently a library was established. (Dion Cass. liii. 1; Horat. Carm. i. 31, Epist. i. 3. 17; Propert. iv. 6. 11; Ov. Ars Am. iii. 389.)