life form

American  

Or life-form

noun

1. the form that is characteristic of a particular organism at maturity.

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life form British  

noun

1. biology the characteristic overall form and structure of a mature organism on the basis of which it can be classified

2. any living creature

3. (in science fiction) an alien

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Etymology

Origin of life form

First recorded in 1850–55

Example Sentences

With “Covenant,” the standout is Fassbender’s villain, although his dual portrayal of Walter, the human crew’s protective synthetic life form, is equally as compelling.

From Salon • Jul. 4, 2025

Space colonisers come face-to-face with a terrifying life form while scavenging the deep ends of a derelict space station.

From BBC • Dec. 9, 2024

Yes, humans, like virtually every life form, have a need to procreate — but in aggregate, not individually.

From Los Angeles Times • Sep. 19, 2024

The new knowledge adds to our understanding of parasites, which could be the most widespread life form on Earth.

From Science Daily • Sep. 17, 2023

Somewhere inside that building lived a Level 4 life form, and it was growing, multiplying, cooking inside hosts.

From "The Hot Zone" by Richard Preston