quinquennĭum, ii, n. [quinquennis], a period of five years, five years (class.): CENSORES MAGISTRATVM QVINQVENNIVM HABENTO, Cic. Leg. 3, 3, 7: tria quinquennia, i. e. fifteen years, Ov. M. 4, 292: duo, id. ib. 12, 584.