lifespan
noun
life·span
ˈlīf-ˌspan 
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
Hummingbirds often have a very short lifespan; most do not live longer than a single year, and those who are lucky enough can live up to four years.
—
Tiffany Acosta, AZCentral.com, 19 Mar. 2026
Since Tuck Everlasting was first published in 1975, the average American’s lifespan has increased from 72 to 80.
—Literary Hub, 18 Mar. 2026
Throughout its lifespan, the station has served as a test bed for scientific research in microgravity and has in years past opened itself up to private commercial missions.
—Eric Lagatta, USA Today, 17 Mar. 2026
Contemporary trends include a dramatic increase in the average human lifespan, the movement of the vast mass of our planet’s population out of poverty, and the spread of democracy.
—Arthur I. Cyr, Chicago Tribune, 17 Mar. 2026
Arevon estimates Nighthawk is expected to deliver more than $30 million in property tax payments that can support schools, infrastructure improvements and other public services over its lifespan.
—Rob Nikolewski, San Diego Union-Tribune, 16 Mar. 2026
Removing rust stains from enamel sinks and tubs keeps your surfaces looking clean and extends their lifespan.
—Caroline Lubinsky, Martha Stewart, 15 Mar. 2026
Surrounding yourself with difficult people could shorten your lifespan, according to new research.
—Angelica Stabile, FOXNews.com, 13 Mar. 2026
Every foam mattress in this guide was tested by our editors and contributors in their own homes—many for years, if not the lifespan of the mattress.
—Bailey Berg, Architectural Digest, 10 Mar. 2026
Examples are automatically compiled from online sources to
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Tiffany Acosta, AZCentral.com, 19 Mar. 2026
Since Tuck Everlasting was first published in 1975, the average American’s lifespan has increased from 72 to 80.
—Literary Hub, 18 Mar. 2026
Throughout its lifespan, the station has served as a test bed for scientific research in microgravity and has in years past opened itself up to private commercial missions.
—Eric Lagatta, USA Today, 17 Mar. 2026
Contemporary trends include a dramatic increase in the average human lifespan, the movement of the vast mass of our planet’s population out of poverty, and the spread of democracy.
—Arthur I. Cyr, Chicago Tribune, 17 Mar. 2026
Arevon estimates Nighthawk is expected to deliver more than $30 million in property tax payments that can support schools, infrastructure improvements and other public services over its lifespan.
—Rob Nikolewski, San Diego Union-Tribune, 16 Mar. 2026
Removing rust stains from enamel sinks and tubs keeps your surfaces looking clean and extends their lifespan.
—Caroline Lubinsky, Martha Stewart, 15 Mar. 2026
Surrounding yourself with difficult people could shorten your lifespan, according to new research.
—Angelica Stabile, FOXNews.com, 13 Mar. 2026
Every foam mattress in this guide was tested by our editors and contributors in their own homes—many for years, if not the lifespan of the mattress.
—Bailey Berg, Architectural Digest, 10 Mar. 2026
Cite this Entry
“Lifespan.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lifespan. Accessed 22 Mar. 2026.
Copy CitationMedical Definition
lifespan
noun
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
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