A lifetime is the entire length of time a person or other living thing is alive. After a famous actor dies, she may be fondly remembered for a lifetime of great movie roles.

Things that take up most of the duration of a person's life are often described using the word lifetime, like a terrible driver's lifetime ban on holding a driver's license, or a lifetime achievement award for all of your accomplishments. You can also talk about the lifetime of an object, or the length of time it's useful, and use lifetime figuratively, to mean "a very long time."

Definitions of lifetime
  1. noun
    the period during which something is functional (as between birth and death)
    synonyms: life, life-time, lifespan
    see moresee less
    afterlife, hereafter
    life after death
    kingdom come
    the next world
    perpetual life after death
    type of:
    period, period of time, time period
    an amount of time
Word Family

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