lifespan

noun

life·​span ˈlīf-ˌspan How to pronounce lifespan (audio)
variants or less commonly life span
plural lifespans also life-spans
Synonyms of lifespannext
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

Synonyms of lifespan

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Examples of lifespan in a Sentence

the average lifespan of house cats increase the human lifespan
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
All of this can lead to higher repair costs, not to mention shortening your vehicle’s lifespan. — Molly Burford, Southern Living, 22 Aug. 2026 This is intended to minimize degradation, reducing contrast decay and improving light projection reliability, ultimately extending the screen's lifespan. — Michael Lydick, PC Magazine, 21 Aug. 2026 Overcleaning certain items, like pillows and walls, can cause unnecessary wear and reduce their lifespan. — Ashlyn Needham, The Spruce, 21 Aug. 2026 Initially, Astromech is focused on understanding longevity, using its model to map 46 genes associated with longer lifespans, cancer resistance and cell maintenance. — Alex Knapp, Forbes.com, 21 Aug. 2026 See All Example Sentences for lifespan

Word History

First Known Use

1831, in the meaning defined at sense 2

Time Traveler
The first known use of lifespan was in 1831

Rhymes for lifespan

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Browse Nearby Words

lifesome
lifespan
life story
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Cite this Entry

“Lifespan.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lifespan. Accessed 23 Aug. 2026.

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Kids Definition

life span

noun
: the average length of life of a living thing or of the persistence of a material object under specified circumstances or in a particular environment

Medical Definition

lifespan

noun
ˈlīf-ˌspan How to pronounce lifespan (audio)
variants also 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
Last Updated: - Updated example sentences
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