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 partJoseph 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.
By contrast, measuring the lengths of submillimeter organisms has typically involved taking multiple images under a microscope and conducting image analysis. ArsTechnica, 21 June 2025 Salmonella is an organism that can cause serious and fatal infections in children, the elderly and others with weakened immune systems, according to the CDC. Natalie Neysa Alund, USA Today, 18 June 2025 One such host organism is Pichia pastoris, a species of yeast originally isolated in France in 1950. Lucy Notarantonio, MSNBC Newsweek, 18 June 2025 While bees are the main pollinator of plants, there are other organisms that augment pollination, namely butterflies, hummingbirds, flies, wasps, bats and beetles. The San Diego Union Tribune, San Diego Union-Tribune, 14 June 2025 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

Cite this Entry

“Organism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/organism. Accessed 1 Jul. 2025.

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

More from Merriam-Webster on organism

Last Updated: - Updated example sentences
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