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1610s, from Late Latin longaevitatem (nominative longaevitas) "great age, long life," from Latin longaevus "long-lived," from longus (see long (adj.)) + aevum "lifetime, age" (see eon).
longevity lon·gev·i·ty (lŏn-jěv'ĭ-tē)n. Duration of an individual life beyond the norm for the species.