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

2 of 2

adjective

variants or less commonly organismal
1
: of or belonging or relating to an organism especially as a functional whole
2
: of or relating to organicism or organic mechanism : holistic
the organismic theory of the state

Examples of organism in a Sentence

Noun A human being is a complex organism.
Recent Examples on the Web
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Noun
Elusive but important Fungi are essential organisms that contribute to Earth’s carbon cycle and support the health and nutrition of many plant species. — Mindy Weisberger, CNN Money, 23 Oct. 2026 To overcome these limitations, the UMass Amherst researchers adopted a different approach, inspired by how living organisms distribute energy production throughout their tissues. — New Atlas, 23 Oct. 2026 The abnormal warmth is also delaying the changing of many tree leaves, and could bring health implications for plants across the Midwest and certain organisms living in the Great Lakes. — Finnegan Belleau, Chicago Tribune, 21 Oct. 2026 Calorie reduction reliably improves health and lifespan in many organisms, including yeast, worms, flies and rodents. — Rowan Jacobsen, Scientific American, 20 Oct. 2026 See All Example Sentences for organism

Word History

First Known Use

Noun

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 27 Oct. 2026.

Kids Definition

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

Medical Definition

: an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent : a living being
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