1

lifetime

noun life·time \ ˈlīf-ˌtīm \
|Updated on: 22 Jun 2018

Definition of lifetime

1 a : the duration of the existence of a living being (such as a person or an animal) or a thing (such as a star or a subatomic particle)
b : life 12
2 : an amount accumulated or experienced in a lifetime
  • a lifetime of regrets

Examples of lifetime in a Sentence

  1. a lifetime spent traveling the world

  2. It would have taken me a lifetime to read all those books.

  3. Childhood seems a lifetime ago now!

  4. a chemical with a lifetime of only a few minutes

  5. the lifetime of a planet

Recent Examples of lifetime from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lifetime.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of lifetime

13th century

in the meaning defined at sense 1a

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lifetime Synonyms


2

lifetime

adjective

Definition of lifetime

1 : lifelong
2 : of long duration or continuance
  • lifetime legislation
3 : measured or achieved over the span of a career
  • a baseball player's lifetime batting average

First Known Use of lifetime

1834

in the meaning defined at sense 1

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NEW! Time Traveler


LIFETIME Defined for English Language Learners

lifetime

Definition of lifetime for English Language Learners

  • : the time during which a person is alive

  • : a very long time

  • : the time during which something lasts or is useful


LIFETIME Defined for Kids

lifetime

noun life·time \ ˈlīf-ˌtīm \

Definition of lifetime for Students

: life 2


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