organism

1 of 2

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

organismic

2 of 2

adjective

or·​ga·​nis·​mic ¦ȯ(r)gə¦nizmik How to pronounce organismic (audio)
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
organismically adverb

Examples of organism in a Sentence

Noun A human being is a complex organism.
Recent Examples on the Web
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Noun
Wilt Diseases Of Tomatoes Disease organisms that produce symptoms of wilt in tomatoes include fungal, bacterial and viral agents. Kim Toscano, Southern Living, 21 June 2026 The recent algae bloom in the National Mall's Reflecting Pool highlights a common issue with these diverse, photosynthetic organisms. Marshall Shepherd, Forbes.com, 21 June 2026 Algae are important and beneficial organisms when the ecosystem is in balance. Los Angeles Times, 20 June 2026 Listeria is an organism that can cause serious and sometimes fatal infections in young children, frail or elderly people, or others with weakened immune systems. Greta Cross, USA Today, 19 June 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 25 Jun. 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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