microorganism

noun
mi·​cro·​or·​gan·​ism | \ -ˈȯr-gə-ˌni-zəm \

Definition of microorganism

: an organism (such as a bacterium or protozoan) of microscopic or ultramicroscopic size

Examples of microorganism in a Sentence

Recent Examples on the Web

Pulling It Together Pathogens hitch rides on hosts, spreading microorganisms such as bacteria and viruses. Mallory Locklear, Discover Magazine, "With Big Data and Predictive Analytics, Scientists Are Getting Smarter About Outbreaks," 8 Nov. 2018 The ice in Greenland is also getting darker, as soot carried through the air and microorganisms like algae coat the ice. Umair Irfan, Vox, "Greenland’s ice sheet is melting at its fastest rate in centuries," 8 Dec. 2018 The agency already had extensive experience with insulins as well as drugs derived from microorganisms, and the FDA viewed recombinant DNA techniques as an extension, or refinement, of these methods. Henry I. Miller, WSJ, "Follow the FDA’s Self-Interest," 28 Oct. 2018 Given these facts, the early moon looks like a potential paradise for microorganisms. Avery Thompson, Popular Mechanics, "Life May Have Once Existed on the Moon," 24 July 2018 Only now, with the background knowledge that (a) bacteria make a lot of bioactive compounds, many of which do combat other microorganisms, and that (b) phages are a major scourge for bacteria, did researchers think to check. Diana Gitig, Ars Technica, "Bacteria engage in chemical warfare against viruses," 5 Dec. 2018 The whole category is based on a molecule called beta-lactam, which is naturally secreted by the Penicillium chrysogenum fungus, giving the species a competitive advantage against other microorganisms in the wild. Jonathon Keats, Discover Magazine, "Bacteria That Eat Drugs Could Help Solve the Antibiotic Resistance Crisis," 8 Nov. 2018 This new protein family is even found in bacteria and other microorganisms that were never known to sense light until now. Shandria Sutton, Science | AAAS, "New ‘light-eating’ protein discovered in the Sea of Galilee," 5 July 2018 The cause is unknown, but earlier studies conclude that the skin microbiome -- the community of all the bacteria and other microorganisms living on the surface of the skin -- plays a major role. Ian Myles, CNN, "A possible new weapon against eczema: live bacteria," 17 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'microorganism.' 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 microorganism

1880, in the meaning defined above

History and Etymology for microorganism

International Scientific Vocabulary

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Last Updated

28 Dec 2018

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Time Traveler for microorganism

The first known use of microorganism was in 1880

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More Definitions for microorganism

microorganism

noun

English Language Learners Definition of microorganism

biology : an extremely small living thing that can only be seen with a microscope

microorganism

noun
mi·​cro·​or·​gan·​ism | \ ˌmī-krō-ˈȯr-gə-ˌni-zəm \

Kids Definition of microorganism

: a living thing (as a bacterium) that can only be seen with a microscope

microorganism

noun
mi·​cro·​or·​gan·​ism | \ -ˈȯr-gə-ˌniz-əm \

Medical Definition of microorganism

: an organism of microscopic or ultramicroscopic size

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More from Merriam-Webster on microorganism

Spanish Central: Translation of microorganism

Nglish: Translation of microorganism for Spanish Speakers

Britannica.com: Encyclopedia article about microorganism

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