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

The warm sunny weather has many flocking to the beach, but as the Fourth of July holiday weekend approaches, officials in Florida are warning beachgoers of an unpleasant organism lurking in the water along part of the coast. Caitlin O'kane, CBS News, "Sea lice reported on Florida beach," 27 June 2018 Because ticks that carry Lyme can also carry other infectious organisms through the same bite, the doctor tested Gus for coinfections. Cathy Cassata, Fox News, "This family learned tick bites can transmit more than Lyme disease," 23 June 2018 Spinoffs are nothing new, of course; network TV is an adaptive organism, automatically straining to survive whatever obstacles get in its way. Matthew Gilbert,, "A wait-and-see approach on ‘The Conners’," 22 June 2018 As part of the sponges’ natural defense against other organisms invading their space, these microbes produce compounds that keep the invaders away and sponges thriving undersea. Anne Geggis,, "Sea sponges may hold key to fighting killer infections," 22 June 2018 This Last-Resort Medical Treatment Offers Hope Phages are ubiquitous viruses—there are more of them than any other organism in the world—that fight bacteria. Alexandra Sifferlin, Time, "Scientists Are Using a New Weapon to Fight Drug-Resistant Bacteria—Viruses," 21 June 2018 Knowing an organism’s genome could help bring it back from extinction, at least theoretically. Bryn Nelson /, NBC News, "The audacious plan to catalog all life on Earth," 14 June 2018 The marsh provided an environment for salmonella bacteria and other organisms capable of causing typhoid fever and paratyphoid fever. Allan B. Schwartz,, "Medical Mystery: Did this president suffer a death by cherries?," 3 May 2018 The D’Antoni System is an evolving organism, shifting with the principals and the times. Lee Jenkins,, "Space City: How Faith Fuels the Rockets' Explosive Offense," 1 May 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

16 Sep 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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Comments on organism

What made you want to look up organism? Please tell us where you read or heard it (including the quote, if possible).


alleviating pain or harshness

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