Lewis & Short

aevĭtas, ātis, f. [aevum] (an old word, = aetas, which is contr. from it), the time through which a person lives or a thing lasts, the time of existence.

  1. I. Lit.: qua voluptate aevitatis extimam attigit metam aevitas, Varr. ap. Non. p. 193, 7: censores populi aevitates, suboles, familias pecuniasque censento, Cic. Leg. 3, 7: SI MORBVS AEVITASVE VITIVM ESCIT, Leg. XII. Tab. ap. Gell. 20, 1, 25; Arn. 5, 8.
  2. II. Trop.
    1. A. Of the future, time unending, immortality: sed etiam mortales deos ad aevitatem temporis edidit, for endless ages, to endure forever, App. Dogm. Plat. 1, 120.
    2. B. Of the past: quid operis aut negotii celebrans anteacti temporis decurrerit aevitatem, the time of yore, Arn. 2, 22.