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Mĕro, ōnis, m. [merum], the wine-bibber, a nickname bestowed on the emperor Tiberius Claudius Nero, in allusion to his drinking propensities: propter nimiam vini aviditatem, pro Tiberio Biberius, pro Claudio Caldius, pro Nerone Mero vocabatur, Suet. Tib. 42.