microorganism

noun
mi·​cro·​or·​gan·​ism | \ ˌmī-krō-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

Surprisingly, the distinctive smell of human sweat results from a cocktail of microorganisms, living in and on our bodies, that metabolize sweat into body odor. Paul Vanouse, The Conversation, "An artist’s journey into the science of sweat," 12 Sep. 2019 Unlike regular plastic, a petroleum product, bioplastic is made from plants or engineered by microorganisms. Krista Kafer, The Denver Post, "Kafer: Single-use plastic is a problem but a bag ban is not the answer, not yet," 22 Aug. 2019 Each chamber will be seeded with microorganisms that thrive in high-pressure terrestrial environments. Shannon Stirone, Scientific American, "New NASA Mission Will Fly Titan’s Frigid Skies to Search for Life’s Beginnings," 27 June 2019 Research from this year has suggested that the icy Enceladus in particular has strong potential for life, with microorganisms clinging to the surface of its seafloor. David Grossman, Popular Mechanics, "Here's AI's Best Guess at a 3D-Printed Lander for Saturn and Jupiter's Moons," 14 Nov. 2018 Van Diepen doesn’t like techniques that use plastic or herbicides to kill the the grass because those also kill the microorganisms that help create healthy soil. Los Angeles Times, "Don’t pull the weeds in Rainbeau Mars’ edible garden," 12 Sep. 2019 Over a year, Blackley and his colleagues collected samples from these pots and studied the microorganisms within them. Caitlin O'kane, CBS News, "Scientist bakes sourdough bread with 4,500-year-old yeast found in Egyptian pottery," 7 Aug. 2019 Moreover, the Beresheet mission was hardly the first time anyone delivered microorganisms to the Moon. Robert Zubrin, National Review, "‘Tardigrades on the Moon Is Not Good’," 31 Aug. 2019 Panspermia is the hypothesis that life on Earth originated from microorganisms in outer space that were carried here unintentionally by objects such as space dust, meteoroids and asteroids, according to an article on NASA's website. Fox News, "Meteorite strikes made life on Earth possible, study says," 14 Aug. 2019

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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Statistics for microorganism

Last Updated

5 Oct 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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