organism

American  

[awr-guh-niz-uhm] / ˈɔr gəˌnɪz əm /

noun

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 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

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

Etymology

Origin of organism

First recorded in 1655–65; organ + -ism

Example Sentences

Grace is sent into space on a one-way mission to stop the spread of an energy-consuming organism called Astrophage, which threatens to create a new Ice Age on Earth.

From The Wall Street Journal • Apr. 3, 2026

She added that the drugs did not provide effective coverage against a Gram-positive organism, which was the most likely pathogen causing the infection.

From BBC • Mar. 11, 2026

Genetic analysis confirmed that the organism represents not only a newly identified species but also an entirely new genus.

From Science Daily • Mar. 6, 2026

Scientists refer to this organism as the "last universal common ancestor," and it represents the earliest form of life that can currently be examined using established evolutionary methods.

From Science Daily • Feb. 10, 2026

If she were to perceive their true form, they would seem more like architecture than organism, like huge structures composed of intelligence and feeling.

From "The Subtle Knife" by Philip Pullman

Related Words

• animal
• creature
• structure