Charlton T. Lewis, Charles Short, A Latin Dictionary

I.of or belonging to the best or noblest, aristocratic: “res publica, quae ex tribus generibus illis, regali et optumati et populari confusa modice,” Cic. Rep. 2, 23, 41 (from Non. 342, 31): matronae opulentae, optimates, Enn. ap. Cic. Fam. 7, 6, 1 (Trag. v 294 Vahl.).—Hence, subst.: optĭmas (optŭm- ), ātis, usually in plur.: optĭmātes (optŭm- ), um and ĭum, comm., the adherents of the best men, in a political sense, i. e. the aristocratic party, the aristocrats (opp. populares, the popular party; cf.: “primores, proceres): qui ita se gerebant, ut sua consilia optimo cuique probarent, optimates habebantur ... sunt principes consilii publici, sunt, qui eorum sectam sequuntur,” Cic. Sest. 45, 96: “cum (summa rerum) est penes delectos, tum illa civitas optimatium arbitrio regi dicitur (opp. to the regnum and the civitas popularis),” id. Rep. 1, 26, 42; so, “in optimatium dominatu,” id. ib. 1, 27, 43: “contra voluntatem omnium optimatum,” id. Inv. 2, 17, 52: “plebis, et optimatium certamina,” Tac. A. 4, 32: “omnes optimates Juda et Jerusalem,” Vulg. Jer 27, 20 et saep.—In sing.: dum pudet te parum optimatem esse, Cael. ap Cic. Att. 10, 9, A, 2.