biosphere

American  

[bahy-uh-sfeer] / ˈbaɪ əˌsfɪər /

noun

1. the part of the earth's crust, waters, and atmosphere that supports life.

2. the ecosystem comprising the entire earth and the living organisms that inhabit it.

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biosphere British  

/ ˈbaɪəˌsfɪə /

noun

1. the part of the earth's surface and atmosphere inhabited by living things

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biosphere Scientific  

/ bī′ə-sfîr′ /

1. The parts of the land, sea, and atmosphere in which organisms are able to live. The biosphere is an irregularly shaped, relatively thin zone in which life is concentrated on or near the Earth's surface and throughout its waters.

2. All the Earth's ecosystems considered as a single, self-sustaining unit.

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biosphere Cultural  

1. The thin outer shell of the Earth and the inner layers of its atmosphere; the place where all living systems are found.

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Related Words

See ecosystem ( def. ).

Other Word Forms

• biospheric adjective

Etymology

Origin of biosphere

First recorded in 1895–1900; from German Biosphäre; bio-, -sphere

Explanation

A biosphere is a place where organisms live. You wouldn't want to travel beyond the earth's biosphere, unless of course you are an astronaut. From the Greek bios, "life," and sphaira, "sphere," biosphere came into English use in the 19th century. It means the life that occurs within a certain sphere or region around a planet. If you're reading this from Mars you probably have a biosphere all your own. You and other living things on Earth need oxygen and other substances to survive, and the biosphere fulfills those needs.

Example Sentences

The island was designated a Unesco biosphere reserve in 2019, which recognises the sustainable ways in which local people work with their natural environment.

From BBC • Apr. 8, 2026

By demonstrating how urea could form naturally under Archean conditions and showing that it acts as both a nutrient and an inhibitor, the researchers revealed how subtle chemical balances shaped Earth's early biosphere.

From Science Daily • Nov. 2, 2025

Various forms of evidence suggest that the biosphere was more productive during the Miocene compared to now, and that at higher latitudes, this effect was more pronounced.

From Salon • Feb. 17, 2025

In contrast, land habitats make up less than 1 percent of the planet’s biosphere because the band of life is so narrow, making its volume quite small.

From New York Times • May 30, 2024

The aids virus and other emerging viruses are surviving the wreck of the tropical biosphere because they can mutate faster than any changes taking place in their ecosystems.

From "The Hot Zone" by Richard Preston

Related Words

• cave
• dwelling
• environment
• haven
• nest
• surroundings
• terrain
• territory