nūbēcŭla, ae, f. dim. [nubes], a little cloud.
I Lit., Plin. 18, 35, 82, § 356.—
B Transf., something cloudy or dark, a dark spot : mala urina, in quā veluti furfures atque nubeculae apparent, Plin. 28, 6, 19, § 68: smaragdi variā nubeculā improbati, id. 37, 5, 18, § 68: nubeculae et caligationes suffusionesque oculorum, id. 29, 6, 38, § 123; 20, 7, 26, § 61.—
II Trop., a gloomy expression of countenance : frontis tuae nubecula, Cic. Pis. 9, 20.