Lewis Short
(verb) : sĕrēno, āvi, ātum, 1, 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. poët. 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.
Charlton T. Lewis, Charles Short, A Latin Dictionary