life·​time | \ˈlīf-ˌtīm \

Definition of lifetime 

(Entry 1 of 2)

1a : 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 sense 12

2 : an amount accumulated or experienced in a lifetime a lifetime of regrets



Definition of lifetime (Entry 2 of 2)

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

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Synonyms for lifetime

Synonyms: Noun

continuance, date, duration, life, life span, run, standing, time

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Examples of lifetime in a Sentence


a lifetime spent traveling the world It would have taken me a lifetime to read all those books. Childhood seems a lifetime ago now! a chemical with a lifetime of only a few minutes the lifetime of a planet
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Recent Examples on the Web: Noun

China, during my lifetime, has largely been a win-win partner. Eric Johnson, Recode, "Why tech companies need to reinvent themselves every three to four years," 10 Oct. 2018 The Fixer Upper alum gave fans the surprise of a lifetime on Thursday during Reese Witherspoon's visit to Magnolia Market. Jessica Leigh Mattern, Country Living, "Joanna Gaines Steps Out for Her First Major Public Appearance Since Giving Birth to Crew," 29 Sep. 2018 McCain was born in 1936, at a Navy base in the Panama Canal Zone, a literal child of U.S. imperialism whose father and grandfather were both Navy admirals during their lifetimes. Prince Shakur, Teen Vogue, "The Legacy Left Behind by John McCain Is Imperfect Yet Impactful," 27 Aug. 2018 Which president has done the best job during your lifetime? James Hohmann, Washington Post, "The Daily 202: Toothless trade resolution demonstrates Congress’s unwillingness to check Trump," 12 July 2018 Zuckerberg and wife Priscilla Chan have pledged to give away 99 percent of Facebook stock during their lifetime. Jessica Guynn, USA TODAY, "Mark Zuckerberg is richer than Warren Buffett (but not as rich as Jeff Bezos or Bill Gates)," 6 July 2018 Along with 5,000 acres, his mansion, his cattle and honeybees, Jefferson owned over 600 individuals during his lifetime. Samantha Willis, Glamour, "Thomas Jefferson Owned Hundreds of Slaves. Now, a Black Woman Will Run His Foundation.," 29 June 2018 Herbert Archer Richardson, an entrepreneur who acquired tens of thousands of acres and as many as seven sailing ships during his lifetime, came to the area in about 1876 and established himself at nearby Stewarts Point. Peter Fimrite,, "Family’s legendary grove of old-growth redwoods preserved," 26 June 2018 During their lifetimes, bogong moths that survive to do so will make a pair of 1,000km journeys. The Economist, "The first clear evidence of a sense of magnetism in insects," 21 June 2018

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.

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First Known Use of lifetime


13th century, in the meaning defined at sense 1a


1834, in the meaning defined at sense 1

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Statistics for lifetime

Last Updated

7 Dec 2018

Look-up Popularity

Time Traveler for lifetime

The first known use of lifetime was in the 13th century

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More Definitions for lifetime



English Language Learners Definition of lifetime

: the time during which a person is alive

: a very long time

: the time during which something lasts or is useful


life·​time | \ˈlīf-ˌtīm \

Kids Definition of lifetime

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More from Merriam-Webster on lifetime

Rhyming Dictionary: Words that rhyme with lifetime

Thesaurus: All synonyms and antonyms for lifetime

Spanish Central: Translation of lifetime

Nglish: Translation of lifetime for Spanish Speakers

Britannica English: Translation of lifetime for Arabic Speakers

Comments on lifetime

What made you want to look up lifetime? Please tell us where you read or heard it (including the quote, if possible).


a soft lustrous wool fabric with mohair

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