organism

noun

or·​gan·​ism ˈȯr-gə-ˌni-zəm How to pronounce organism (audio)
1
: a complex structure of interdependent and subordinate elements whose relations and properties are largely determined by their function in the whole
The nation is not merely the sum of individual citizens at any given time, but it is a living organism, a mystical body … of which the individual is an ephemeral part …Joseph Rossi
2
: an individual constituted to carry on the activities of life by means of parts or organs more or less separate in function but mutually dependent : a living being
a multicellular organism
organismic adjective
or less commonly organismal
organismically adverb

Examples of organism in a Sentence

A human being is a complex organism.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The study highlights a shift in bioengineering approaches, moving from single-organism engineering toward cooperative microbial systems that behave like living electrical circuits. Neetika Walter, Interesting Engineering, 17 Apr. 2026 Cyanobacteria, sometimes called blue-green algae, are microscopic organisms that thrive in warm, nutrient-rich water. Jacob Wycoff, CBS News, 17 Apr. 2026 The pair have invented a Bioluminator that detects and amplifies bioluminescence — the biochemical emission of light by living organisms. Brady MacDonald, Oc Register, 17 Apr. 2026 Because of the intricacies of predator-prey relationships, impacts on individual organisms will ripple across the ecosystem, Grosell said. Asuka Koda, CNN Money, 17 Apr. 2026 See All Example Sentences for organism

Word History

First Known Use

circa 1774, in the meaning defined at sense 1

Time Traveler
The first known use of organism was circa 1774

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Cite this Entry

“Organism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/organism. Accessed 20 Apr. 2026.

Kids Definition

organism

noun
or·​gan·​ism ˈȯr-gə-ˌniz-əm How to pronounce organism (audio)
1
: something having many related parts that function together as a whole
2
: an individual living thing that carries on the activities of life by means of organs which have separate functions but are dependent on each other : a living person, plant, or animal
organismic adjective

Medical Definition

organism

noun
or·​gan·​ism ˈȯr-gə-ˌniz-əm How to pronounce organism (audio)
: an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent : a living being
organismic adjective
also organismal
organismically adverb

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