Lewis Short
(adjective) : mercēdŏnĭus, a, um, 1. merces-do
* Of or belonging to the payment of wages: Mercedonios (dies) dixerunt a mercede solvendā, on which wages are paid, pay-days, Paul. ex Fest. p. 124 Müll.
* Subst.: mercēdŏnĭus, ii, m., a payer of wages, paymaster: mercedonius, qui solvit mercedem; ‡ mercedarius (an employer), qui dat mercedem pro labore sibi impenso, Gloss. Isid. 37.
* Mercēdŏnĭus or Mercēdī-nus, = Μερκηδόνιος, Μερκεδῖνος, mensis, an intercalary month of 22 or 23 days, inserted every two years in the calendar of Numa, Vet. Kalend. Rom. ap. Grut. 133; cf. so Laur. Lyd. de Mens. 4, 92.
Charlton T. Lewis, Charles Short, A Latin Dictionary