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

Synonyms of lifespan

• duration
• life
• lifetime
• time

Examples of lifespan in a Sentence

the average lifespan of house cats

increase the human lifespan

Recent Examples on the Web

Calorie reduction reliably improves health and lifespan in many organisms, including yeast, worms, flies and rodents. — Rowan Jacobsen, Scientific American, 20 Oct. 2026

Historically, empires have varied so widely in size and lifespan that no one model fits all. — Niall Ferguson, Foreign Affairs, 20 Oct. 2026

Essentially, the brushless system reduces friction and extends the lifespan of the motor. — New Atlas, 20 Oct. 2026

That question motivated Clark to better understand aging among plants and animals and to look for hints to extend humans' lifespan. — Kyle Melnick The Washington Post, Arkansas Online, 18 Oct. 2026

Word History

First Known Use

1831, in the meaning defined at sense 2

Rhymes for lifespan

• businessman
• canavan
• caravan
• constantan
• dragoman
• fisherman
• handyman
• harmattan
• journeyman
• marianne
• middleman
• minivan

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 

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