sĕrēno, āvi, ātum, 1, v. a. [serenus], to make clear, fair, or serene, to clear up (poet.; syn. tranquillo).
I 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. Ach. 1, 120.— Absol. : luce serenanti, in bright , clear daylight , * Cic. poët. Div. 1, 11, 18.—
B Impers. : cum serenat, when it is clear , Min. Fel. 32, 4.—
II Trop.: spem fronte serenat, Verg. A. 4, 477; for which: tristia fronte, Sil. 11, 368; cf.: nubila animi, Plin. 2, 6, 4, § 13.