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Sĭbylla (in many MSS. and edd. Sĭbul-la, e. g. Tac. A. 6, 18 Ritter), ae, f., = Σίβυλλα, a female soothsayer, a prophetess, Sibyl, Varr. ap. Lact. 1, 6, 7; Aug. Civ. Dei, 18, 23; Lact. 2, 8, 48; Verg. A. 5, 735: has (litteras), credo, nisi Sibylla legerit, Interpretari alium potesse neminem, Plaut. Ps. 1, 1, 23: terrae vis Pythiam Delphis incitabat: naturae Sibyllam. Cic. Div. 1, 36, 79; cf. id. ib. 1, 18, 34.
In Roman mythology, the most celebrated is the Sibyl at Cumae, in the service of Apollo; in the time of Æneas, Ov. M. 14, 104 sq.; 14, 154; 15, 712; Verg. A. 6, 10; 6, 98.
A later Sibyl in the time of Tarquinius Superbus, whose predictions were deposited in the Capitol, and in time of danger were consulted by a college of priests, appointed for that special purpose (at first duumviri, afterwards decemviri and quindecemviri, v. h. vv.), Lact. 1, 6; Gell. 1, 19, 1 sqq.; Plin. 13, 13, 27, § 88; Cic. N. D. 3, 2, 5; id. Div. 1, 43, 97 sq.; id. Rab. Post. 2, 4; id. Fam. 1, 7, 4; Liv. 38, 45; Serv. ad Verg. A. 3, 445; Isid. Orig. 8, 8.
A later Sibyl, burnt by Stilicho, Rutil. Itin. 2, 51; cf. Becker, Antiq. 4, p. 49 sq.
Hence, Sĭ-byllīnus (written SIBVLLIN., Inscr. Orell. 2276, p. 394, and Calend. Praenest. M. Apr. ib. tom. ii. p. 389), a, um, adj., of or belonging to the Sibyl, Sibylline: libri, Varr. l. l.; Gell. l. l.; Varr. L. L. 6, § 15 Müll.; Cic. Verr. 2, 4, 49, § 108; Liv. 5, 13; 7, 27; 22, 9; 29, 10; 36, 37; 41, 21 al. (they are called simply libri in Liv. 3, 10; 21, 62; 22, 1; 22, 36; 22, 57; and libri fatales, id. 22, 10): vaticinationes, Cic. N. D. 2, 3, 10: versus, id. Div. 1, 2, 4; Hor. C. S. 5: fata, Cic. Cat. 3, 4, 9.