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

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

The organism, named Algophthora mediterranea, is a microscopic chytrid fungus that can infect a wide variety of hosts.

From Science Daily • Mar. 6, 2026

When fossil evidence existed for a particular organism, the scientists used its estimated age to anchor that branch of the tree.

From Science Daily • Feb. 18, 2026

In other words, once an intimate symbiotic relationship forms — in which at least one organism depends on another for survival — it’s locked in.

From Los Angeles Times • Feb. 10, 2026

The consequences of uncoupling could indeed be disastrous for any organism from embryo to adult: in time it could lead to the death of the tissue or even of the organism.

From "Silent Spring" by Rachel Carson

Related Words

• animal
• creature
• structure