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in-faustus, a, um, adj., unfortunate, unpropitious (poet. and post-Aug.): infaustas exurite puppes, Verg. A. 5, 635: nomen, id. ib. 7, 717: auspicium, id. ib. 11, 347: gradus, Ov. M. 3, 36: dies, Tac. H. 2, 91: castra, id. A. 1, 30.
Neutr. subst.: in-faustum, i, n., a misfortune: infausto Atheniensium, Plin. 16, 36, 66, § 169.
Adv.: infaustē, unfortunately (late Lat.), Cassiod. An. 12.