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

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

Tourists from Europe and Asia could see they were witnessing something real—a functioning human organism moved by a shared spirit.

From The Wall Street Journal • Jun. 18, 2026

The multi-eyed organism will serve as the centerpiece of “the N.E.S.T.,” an EIT-designed section of Meow Wolf’s new 26,000-square-foot immersive exhibition space.

From Los Angeles Times • May 20, 2026

Weismann called this hereditary material germplasm and argued that it was the only method by which an organism could generate another organism.

From "The Gene" by Siddhartha Mukherjee

Related Words

• animal
• creature
• structure