ob-nūbĭlo

āvi, ātum, 1
I. v. a., to cover with clouds or fog; to overcloud, darken, obscure (post-class.): vultūs serenitatem, Gell. 1, 2, 5: haec omnia vitium, Amm. 28, 4, 2: odore sulfuris obnubilatus, App. M. 9, p. 228, 22; so, animam, id. ib. 8, p. 204, 38.
Lewis & Short
A Latin Dictionary, 1879
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