microorganism

noun
mi·​cro·​or·​gan·​ism | \ -ˈȯr-gə-ˌni-zəm How to pronounce microorganism (audio) \

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

But equally important is how the off-earth environment impacts the microorganisms in our bodies and all around us. John Wenz, Popular Mechanics, "Living in Space Doesn't Turn Bacteria into Killer Superbugs, Study Says," 9 Jan. 2019 The eczema study is the latest in a flood of research in the past several years on the skin microbiome—the microscopic ecosystem containing trillions of bacteria, fungi, viruses and other microorganisms that live on our skin—showing how... Susan Kitchens, WSJ, "Bacteria May Offer New Hope for Treating Skin Disorders," 5 Feb. 2019 Most of the lifeforms discovered are bacteria and other single-cell microorganisms, such as archaea, but their sheer mass equals roughly 15 to 23 billion tonnes of carbon—more than humanity's total imprint on the surface. Sam Blum, Popular Mechanics, "Vast Ecosystem of Underground Organisms Holds More Life Than Earth's Oceans," 11 Dec. 2018 This allows the ice to absorb more solar energy, thereby heating up and melting faster, which in turn allows the microorganisms to spread further. Umair Irfan, Vox, "Greenland’s ice sheet is melting at its fastest rate in centuries," 8 Dec. 2018 But the microorganisms inhabiting our intestines have no such problems. SELF, "Why This Registered Dietitian Tells (Some of) Her Patients to Avoid Kale Salads," 30 Nov. 2018 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

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

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Last Updated

23 Feb 2019

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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 How to pronounce microorganism (audio) \

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 How to pronounce microorganism (audio) \

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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