life span

American  

noun

1. the longest period over which the life of any organism or species may extend, according to the available biological knowledge concerning it.

2. the longevity of an individual.

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life span British  

noun

1. the period of time during which a human being, animal, machine, etc, may be expected to live or function under normal conditions

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Etymology

Origin of life span

First recorded in 1915–20

Example Sentences

If a disease is particularly rare or has a short life span, there isn’t much ‘water’ going into the tub, and there is a big drain on the other side.

From Barron's • Mar. 12, 2026

These burrow-dwelling rats have a maximum life span of nearly 40 years, making them world's the longest-lived rodent.

From BBC • Oct. 9, 2025

Technological advances may turn back aging, extending the average life span by at least a decade.

From The Wall Street Journal • Oct. 3, 2025

But subsequent analyses show this variant is not necessary or sufficient to extend life span.

From Science Magazine • Nov. 20, 2024

But whereas I thought the big news today was Grandpa’s eloping, the first thing Papa said was something about the average life span in America being forty-seven years.

From "Cold Sassy Tree" by Olive Ann Burns