serēno, āvi, ātum, 1, v. a. id., to make clear, fair, or serene, to clear up (poet.; syn. tranquillo). Lit.: vultu, quo caelum tempestatesque serenat (Juppiter), Verg. A. 1, 255: axem, Sil. 12, 637: Olympum, id. 12, 665: glauca terga aquae, Claud. de Apono, 36: domum largo igne, to ligth up, Stat. Achill. 1, 120.

—Absol.: luce serenanti, in bright, clear daylight, * Cic. poet. Div. 1, 11, 18.

— Impers.: cum serenat, when it is clear, Min. Fel. 32, 4.

— Trop.: spem fronte serenat, Verg. A. 4, 477; for which: tristia fronte, Sil. 11, 368; cf.: nubila animi, Plin. 2, 6, 4, § 13.