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.
The team showed that this gliding persists down to –15 degree Celsius, setting a new benchmark for cellular motility in complex, nucleus-bearing organisms. Kaif Shaikh, Interesting Engineering, 10 Sep. 2025 The mottling on the rock could indicate that ancient chemical reactions occurring within it once supported microbial organisms. Ashley Strickland, CNN Money, 10 Sep. 2025 Audiences often identify the creative core of a band with its songwriters or most visible performers who are often one and the same, but groups are organisms that rely on the positive interactions of the participants to achieve commercial results. Mike Alleyne, Forbes.com, 10 Sep. 2025 The crew is being hunted by an organism that can inhabit anyone nearby and mimic its prey. Echo Apsey, Space.com, 9 Sep. 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 12 Sep. 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

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