Mĕro

ōnis, m.

merum

I. 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.
Lewis & Short
A Latin Dictionary, 1879
An open-access project