octōdĕcim

I. card. num. adj. [octo-decem], eighteen (mostly post-class, for duodeviginti): tetrachma Attica centum octodecim milia, Liv. 39, 5, 14: cohortes, Front. Strat. 2, 5, 37; Eutr. 1, 1.
Lewis & Short
A Latin Dictionary, 1879
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