Lewis & Short

quā̆drāgintā, num. adj. [quattuor], forty: quattuor quadraginta minae, Plaut. Most. 3, 1, 102: annos natus, Cic. Rosc. Am. 14, 39; id. Rep. 2, 30, 52: jugera arvi, Cat. 115, 2; Col. 5, 2, 10; 5, 1, 13.