ē-lūcubro

āvi, ātum, 1, v. a.
I. epistolam, quam eram elucubratus, Cic. Att. 7, 19), to compose by lamplight, i. e. at night, with great labor, Cic. Brut. 90 fin.; Tac. Or. 9; Col. 10 praef. fin.
Lewis & Short
A Latin Dictionary, 1879
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