life span


Definition of life span 

1 : the average length of life of a kind of organism or of a material object especially in a particular environment or under specified circumstances

2 : the duration of existence of an individual

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Examples of life span in a Sentence

the average life span of house cats increase the human life span

Recent Examples on the Web

Photo: Mark Reinstein/Corbis via Getty Images Her life spanned. Peggy Noonan, WSJ, "The Secrets of a Great First Spouse," 19 Apr. 2018 What if a longer life span means other, negative health tradeoffs, or simply unexpected side effects and experiments gone wrong? Laura Yan, Popular Mechanics, "This Secretive Harvard Startup is Trying to Reverse Aging," 13 May 2018 In the auto industry, a 10-year model run is akin to the life span of Mithridates. Al Haas,, "Redesigned after 10 years, new Buick Enclave is worth the wait," 28 June 2018 Average life expectancy in McKinley is 74 years, four years less than the typical U.S. life span. Washington Post, "Medicaid Minus Stigma: In Indian Country, It’s Part Of The Fabric Of Life," 2 Apr. 2018 In most cases, combining medication and cognitive behavioral modification treatment is recommended to teach adults effective ways to manage the persistent symptoms across the life span. Rene Hernandez-cardenache, Psy.d., M.s. Ed., miamiherald, "A focus on distraction: A closer look at adult ADHD," 2 July 2018 The current record for the longest human life span was set 21 years ago, when Jeanne Calment, a Frenchwoman, died at the age of 122. Carl Zimmer, New York Times, "How Long Can We Live? The Limit Hasn’t Been Reached, Study Finds," 28 June 2018 Despite these warnings, modest fixes are available, including making small changes in the age of eligibility that recognize lengthening life spans. The Christian Science Monitor, "Shifting views of seniors: less burden, more asset," 27 June 2018 Caloric restriction can increase the median life span of rats by 14 to 45 percent, reducing inflammation, oxidative stress, cholesterol, triglycerides, and the risk of tumors and cardiovascular disease, and improving the immune system. Jacqueline Detwiler, Popular Mechanics, "I Hacked My Body So You Don't Have To," 25 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'life span.' 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 life span

1831, in the meaning defined at sense 2

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Statistics for life span

Last Updated

11 Oct 2018

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Time Traveler for life span

The first known use of life span was in 1831

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More Definitions for life span

life span


English Language Learners Definition of life span

: the amount of time that a person or animal actually lives

life span

\ˈlīf-ˌspan \

Medical Definition of life span 

1 : the duration of existence of an individual

2 : the average length of life of a kind of organism or of a material object especially in a particular environment or under specified circumstances

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