or·​gan·​ism | \ˈȯr-gə-ˌni-zəm \

Definition of organism 

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

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Other Words from organism

organismic \ ˌȯr-​gə-​ˈniz-​mik \ or less commonly organismal \ ˌȯr-​gə-​ˈniz-​məl \ adjective
organismically \ ˌȯr-​gə-​ˈniz-​mi-​k(ə-​)lē \ adverb

Examples of organism in a Sentence

A human being is a complex organism.

Recent Examples on the Web

Moist nooks and crannies full of dead skin cells become the perfect breeding ground for organisms that can cause skin infections, according to the Cleveland Clinic. Caroline Picard, Good Housekeeping, "Test Your Housekeeping Knowledge: How Gross Are Your Cleaning Habits?," 10 July 2018 Getaway Adventures leads the paddling after dark through waters that contain bioluminescent dinoflagellates, small organisms that light up in the water when excited by the movement of the kayaks. Phil Marty,, "Music across the Midwest, rib festival in Indiana and more reasons to hit the road," 30 May 2018 GenX compounds are short-chain PFAS molecules, with only six carbon atoms, and some research indicated that a shorter chain might be less toxic and less likely to build up in organisms. Ken Otterbourg, Fortune, "Teflon’s River of Fear," 24 May 2018 This organism isn't an animal, plant or fungus but a eukaryote. Ashley Strickland, CNN, "Meet the top 10 new species of 2018," 23 May 2018 And in 2016, a team led by Macquarie University researcher Chris Reid showed that slime molds can solve the two-armed bandit problem—a decision-making test normally reserved for organisms with brains. Michael Greshko, National Geographic, "Brainless Creatures Can Do Some Incredibly Smart Things," 21 May 2018 Ginkgo designs organisms using genetic data, coding them in much the same way computers are programmed. Rebecca Spalding,, "The DNA Cops Who Make Sure the World’s Deadliest Viruses Aren’t Rebuilt," 27 June 2018 This new discovery of frogs frozen in amber along with plants, insects, and other organisms is an incredibly important resource to learn more about the plants and animals living in these forests. Avery Thompson, Popular Mechanics, "This 100-Million-Year-Old Frog Trapped in Amber Shows How Little Frogs Have Changed," 14 June 2018 In other organisms, only the very first cells of the developing embryo (known as totipotent cells) are able to form all the body’s tissues. Elizabeth Pennisi, Science | AAAS, "This one, newly discovered cell can remake a whole animal," 14 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'organism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of organism

circa 1774, in the meaning defined at sense 1

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Statistics for organism

Last Updated

11 Nov 2018

Look-up Popularity

Time Traveler for organism

The first known use of organism was circa 1774

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English Language Learners Definition of organism

: an individual living thing

: a system with many parts that depend on each other and work together


or·​gan·​ism | \ˈȯr-gə-ˌni-zəm \

Kids Definition of organism

: a living thing made up of one or more cells and able to carry on the activities of life (as using energy, growing, or reproducing)


or·​gan·​ism | \ˈȯr-gə-ˌniz-əm \

Medical Definition of organism 

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

Other Words from organism

organismic \ ˌȯr-​gə-​ˈniz-​mik \ also organismal \ -​məl \ adjective
organismically \ -​mi-​k(ə-​)lē \ adverb

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