The Collaborative International Dictionary of English v.0.48:
Lifetime \Life"time`\ (l[imac]f"t[imac]m`), n. The time that life continues. [1913 Webster]WordNet (r) 3.0 (2006):
life-time n 1: the period during which something is functional (as between birth and death); "the battery had a short life"; "he lived a long and happy life" [syn: life, lifetime, life- time, lifespan]