mĕsŏnyctĭus

a, um, adj.
I. of midnight: afflatus, Isid. 5, 30, 4.— Hence, subst.: † mĕsŏnyctĭum, ii, n., = μεσονύκτιον, midnight (post-class.): CVIVS MESONYCTIVM FACTVM EST V. ID. DEC., i. e. midnight apparition, Inscr. Mur. 333.
Lewis & Short
A Latin Dictionary, 1879
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