Lewis Short
(adj.Adj.) : festus, a, um, adj.Sanscr. bhas, shine; lengthened from bha-; Gr. φα-, φαίνω, v. for; cf. feriae (fes-iae), orig.
* Of or belonging to the holidays (in opp. to the working-days), solemn, festive, festal, joyful, merry.
* Lit.
* Adj. (syn.: sollennis, fastus).
* Meton., public, solemn, festal, festive, joyous (post-Aug. and rare): dolor,Stat. S. 2, 7, 134: festior annus,Claud. III. Cons. Hon. 3: festissimi dies,Vop. Tac. 11: aures,i. e. gladdened,Claud. B. G. 206 (but in Stat. S. 2, 7, 90 the right read. is fata).
* Subst.: festum, i, n., a holiday, festival; a festal banquet, feast (poet. and late Lat. for dies festus): cur igitur Veneris festum Vinalia dicant, Quaeritis?Ov. F. 4, 877; 1, 190; id. M. 4, 390: forte Jovi festum Phoebus sollenne parabat,feast,id. F. 2, 247: cum dii omnes ad festum magnae matris convenissent,Lact. 1, 21, 25.—In plur.: Idaeae festa parentis erunt,Ov. F. 4, 182: festa venatione absumi,Plin. 6, 22, 24, § 91; Ov. M. 4, 33; 10, 431; Hor. Epod. 2, 59; id. Ep. 2, 2, 197; Vulg. Exod. 23, 14 al.; Greg. Mag. Homil. in Evang. 2, 26, 10; Lact. 1, 22, 24.
Charlton T. Lewis, Charles Short, A Latin Dictionary