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
The team found four distinct turning points in brain development across people's lifespan.
—
Rebecca Ramirez, NPR, 14 Jan. 2026
To be sure, Musk’s confidence about increasing longevity runs contrary to his longtime discomfort with the social consequences of an extended lifespan.
—Marco Quiroz-Gutierrez, Fortune, 14 Jan. 2026
Old Age Leaves have a natural lifespan, like all living things.
—Leanne Potts, Better Homes & Gardens, 14 Jan. 2026
The Sydney study showed that exercise benefits peaked at 50 minutes per day, meaning exercising beyond that wasn’t linked to a longer lifespan.
—Lindsey Leake, NBC news, 13 Jan. 2026
The original plan for Hubble was that it would be retrieved or deorbited by a Space Shuttle mission at the end of its lifespan.
—Chris Young, Interesting Engineering, 13 Jan. 2026
And while lights may seem durable, improper storage can shorten their lifespan.
—Jamie Cuccinelli, Martha Stewart, 13 Jan. 2026
In addition, deep cleaning the crud out of appliances extends lifespan and functionality.
—Mary Marlowe Leverette, The Spruce, 13 Jan. 2026
Why can sleep have such a big impact on your lifespan?
—Korin Miller, SELF, 12 Jan. 2026
Examples are automatically compiled from online sources to
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Rebecca Ramirez, NPR, 14 Jan. 2026
To be sure, Musk’s confidence about increasing longevity runs contrary to his longtime discomfort with the social consequences of an extended lifespan.
—Marco Quiroz-Gutierrez, Fortune, 14 Jan. 2026
Old Age Leaves have a natural lifespan, like all living things.
—Leanne Potts, Better Homes & Gardens, 14 Jan. 2026
The Sydney study showed that exercise benefits peaked at 50 minutes per day, meaning exercising beyond that wasn’t linked to a longer lifespan.
—Lindsey Leake, NBC news, 13 Jan. 2026
The original plan for Hubble was that it would be retrieved or deorbited by a Space Shuttle mission at the end of its lifespan.
—Chris Young, Interesting Engineering, 13 Jan. 2026
And while lights may seem durable, improper storage can shorten their lifespan.
—Jamie Cuccinelli, Martha Stewart, 13 Jan. 2026
In addition, deep cleaning the crud out of appliances extends lifespan and functionality.
—Mary Marlowe Leverette, The Spruce, 13 Jan. 2026
Why can sleep have such a big impact on your lifespan?
—Korin Miller, SELF, 12 Jan. 2026
Cite this Entry
“Lifespan.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lifespan. Accessed 17 Jan. 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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