Nōnĭus, a,
the name of a Roman gens. So M. Nonius Suffenas, Cic. Att. 6, 1, 13.— Nonius Marcellus, a Roman grammarian, whose treatise De Proprietate Sermonis is extant in a very mutilated form .
·noun A <<Vernier>>. ...
Webster's Dictionary of the English Language
, or vernier That fixed to the oblong opening near the lower end of the index-bar of a sextant or ...
The Sailor's Word-Book