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
During the Cambrian explosion, a geologically brief period lasting approximately 53 million years, organisms became more intelligent, biodiversity surged, predators hunted, prey evaded and complex ecosystems emerged. Bratin Saha, Forbes.com, 21 Aug. 2026 This system would have used the same genetic code—the correspondence between nucleic acid sequence and protein sequence—as that used by all organisms today. Philip Ball, Scientific American, 20 Aug. 2026 As water moves through their gills, it is filtered for microscopic organisms that these mollusks then consume as food. Encyclopedia Britannica, 18 Aug. 2026 This is why the Cubs derisively describe Wrigley View Rooftop as a parasite, an organism whose survival depends on the host and that takes from the host without giving back. Michael McCann, Sportico.com, 17 Aug. 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 24 Aug. 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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