organism

American  

[awr-guh-niz-uhm] / ˈɔr gəˌnɪz əm /

noun

• organisms
  plural

1. a form of life composed of mutually interdependent parts that maintain various vital processes.

2. a form of life considered as an entity; an animal, plant, fungus, protistan, or moneran.

3. any organized body or system conceived of as analogous to a living being.

   the governmental organism.

4. any complex thing or system having properties and functions determined not only by the properties and relations of its individual parts, but by the character of the whole that they compose and by the relations of the parts to the whole.

   Synonyms:

   structure, entity, network, organization

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organism British  

/ ˈɔːɡəˌnɪzəm /

noun

1. any living biological entity, such as an animal, plant, fungus, or bacterium

2. anything resembling a living creature in structure, behaviour, etc

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organism Scientific  

/ ôr′gə-nĭz′əm /

1. An individual form of life that is capable of growing, metabolizing nutrients, and usually reproducing. Organisms can be unicellular or multicellular. They are scientifically divided into five different groups (called kingdoms) that include prokaryotes, protists, fungi, plants, and animals, and that are further subdivided based on common ancestry and homology of anatomic and molecular structures.

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Other Word Forms

Derived Forms

• superorganism
  noun
• organismal
  adjective
• organismic
  adjective
• organismally
  adverb
• organismically
  adverb

Inflected Forms

Nouns

• organisms
  plural

Etymology

Origin of organism

First recorded in 1655–65; organ + -ism

Explanation

An organism is a living thing that can function on its own. That includes your pet guppy, the tree in your backyard, and — of course — you. While the word organism typically indicates an actual living thing, you can also use organism to refer to anything that acts or functions like a living thing. For example, the social scene at a high school might be described as "a social organism" because it seems to have a mind of its own — like a living thing or even a vicious animal, depending on where one falls on the popularity scale.

Example Sentences

See Examples For:

organism organisms

"These findings are exciting because they reveal that consumption of a specific amino acid can directly regulate gene expression in an organism by increasing production of a protein enriched in that amino acid," Tavazoie says.

From Science Daily ● Aug. 3, 2026

"The whole organism is an integrated, complex morphology, and each of the individual pieces is interrelated to every other part in the body," Berv said.

From Science Daily ● Jul. 30, 2026

The term is less taxonomically specific and more of a catchall, used to refer to any photosynthesizing organism that isn’t a plant.

From Slate ● Jun. 27, 2026

The organism that is a firm has collections of workers who have process knowledge that is held collectively across the whole workforce and its supply chain.

From Salon ● Jun. 22, 2026

The organic phosphorus insecticides act on the living organism in a peculiar way.

From "Silent Spring" by Rachel Carson

Anderson's research focuses on one of the biggest transitions in biological history: how Earth changed from a planet dominated by bacteria into one inhabited by complex multicellular organisms.

From Science Daily ● Aug. 17, 2026

This period marked a major evolutionary shift from predominantly soft-bodied organisms toward the Cambrian explosion, when animals with greater mobility, shells, and skeletons became increasingly prominent.

From Science Daily ● Aug. 17, 2026

The microscopic organisms can look like blue-green paint, scum or greenish-brown discolouration.

From BBC ● Aug. 12, 2026

Many of these organisms are capable of surviving under extreme conditions, including very high temperatures and strongly acidic or alkaline environments.

From Science Daily ● Aug. 12, 2026

A population of organisms in the wild must have enough natural variation such that winners and losers can be picked.

From "The Gene" by Siddhartha Mukherjee

Related Words

• animal
• creature
• structure