Lewis Short
(adjective) : millēnārĭus, a, um, milleni
* Containing a thousand, millenary (postclass.): numerus, Aug. Civ. Dei, 20, 7: aevum,Tert. de Anim. 32: dux lanceariorum,commander of a thousand,Cassiod. Hist. Eccl. 6, 35.
Charlton T. Lewis, Charles Short, A Latin Dictionary