sĕrēnĭtas, ātis, f. [serenus], clearness, serenity.
I Lit., of the weather, clear , fair , or serene weather; with gen.: cum sit tum serenitas, tum perturbatio caeli, * Cic. Div. 2, 45, 94: diei solisque, Auct. B. Hisp. 29, 4: auctumni, Plin. 18, 35, 80, § 353.— Absol. : tranquilla serenitas (opp. foeda tempestas), Liv. 2, 62, 2; 2, 26, 11: serenitatem praesagire, Plin. 18, 35, 87, § 362; 10, 67, 86, § 188.— Plur. : (vinea) imbribus magis quam serenitatibus offenditur, Col. 3, 1, 10.—
II Trop.
1 Fairness , serenity of fortune, of disposition, etc. (rare; perh. not ante-Aug.): praesentis fortunae, Liv. 42, 62, 4: minor es, quam ut serenitatem meam obducas, Sen. Ira, 3, 25, 4: quantam tempestatem subitā serenitate discussit (principis ortus), Curt. 10, 9, 5.—
2 Serenitas, a title of the Roman emperors , = Serene Highness , Veg. Mil. 3 epil.; Inscr. Grut. 286, 2.