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fēbrŭum, i, n. Orig., in the Sabine lang., a purgation, means of purification.
Hence, februa, ōrum, n., the Roman festival of purification and expiation, celebrated on the 15th of the month hence called February (v. Februarius); whence, Februālis, Febrūlis, and Februāta, surnames of Juno, who was worshipped at this festival; Februātus, the festival itself; and Februus, a surname of Lupercus, who presided over this festival: Lupercalia dicta, quod in Lupercali luperci sacra faciunt. Rex cum ferias menstruas Nonis Februariis edicit, hunc diem Februatum appellat. Februum Sabini purgamentum, et id in sacris nostris verbum; nam et Lupercalia februatio, Varr. L. L. 6, § 13 Müll.; cf. Serv. Verg. A. 8, 343: Ego arbitror Februarium a die Februato, quod tum februatur populus, id est lupercis nudis lustratur antiquum oppidum Palatinum gregibus humanis cinctum, id. ib. 6, § 34; cf. also Paul. ex Fest. p. 85, 13 sq. Müll.: Februa Romani dixere piamina patres, Ov. F. 2, 19; 4, 726; 5, 423: Juno pulchra … nam Fluoniam, Februalemque ac Februam mihi poscere non necesse est, cum nihil contagionis corporeae sexu intemerata pertulerim, Mart. Cap. 2, § 149: Februlis, Paul. ex Fest. p. 85, 16 Müll.; Arnob. 3, p. 118 (dub. al. Februtis).