lifespan

noun

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

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.
This reduces waste, extends product lifespan, and minimizes the use of new materials. Thomas Coughlin, Forbes.com, 15 Sep. 2025 On top of this, a TriTex filtration system makes sure the motor is kept out of harms way to ensure a long lifespan. Alex Harrington, MSNBC Newsweek, 15 Sep. 2025 High-speed charging generates substantial thermal energy, which can accelerate cell degradation, reduce the battery’s overall lifespan, and in rare cases, lead to safety issues like thermal runaway. Aman Tripathi, Interesting Engineering, 14 Sep. 2025 Dish towels can have a short lifespan in the kitchen. Brandee Gruener, Southern Living, 14 Sep. 2025 The timing is particularly crucial because much of the city’s infrastructure has outlasted its lifespan because it was built during the population boom of the 1950s, 1960s and 1970s. David Garrick, San Diego Union-Tribune, 12 Sep. 2025 The plan is to investigate issues across a woman’s lifespan, focusing on areas such as cardiovascular disease, autoimmune conditions, and mental health, including depression and PTSD. Preston Fore, Fortune, 11 Sep. 2025 There’s plenty of research to back the diet’s benefits for weight management, elongating your lifespan and reducing your risk of certain chronic illnesses. Caroline C. Boyle, USA Today, 10 Sep. 2025 Ghost, whose exact age is unknown, is said to be about 4 or 5, which is about the lifespan of the species. Paloma Chavez, Sacbee.com, 9 Sep. 2025

Word History

First Known Use

1831, in the meaning defined at sense 2

Time Traveler
The first known use of lifespan was in 1831

Browse Nearby Words

Cite this Entry

“Lifespan.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lifespan. Accessed 18 Sep. 2025.

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

life span

noun
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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