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nūbĭlo, v. a. and n. [nubilum], to be cloudy or overcast; to make cloudy, to overcast. 
- I.  Lit.: si nubilare coeperit, Varr. R. R. 1, 13, 5.
 
- (β)  Impers. pass.: ubi nubilabitur, Cato, R. R. 88, 2.
 
- B.  Transf., to be cloudy, dull: nubilans fulgor carbunculi, Plin. 37, 7, 25, § 94.
 
- II.  Trop., to cloud over, to obscure (post-class.): lucem dei, Paul. Nol. Carm. 10, 37.