microorganism

noun

mi·​cro·​or·​gan·​ism ˌmī-krō-ˈȯr-gə-ˌni-zəm How to pronounce microorganism (audio)
: an organism (such as a bacterium or protozoan) of microscopic or ultramicroscopic size

Example Sentences

Recent Examples on the Web Such microorganism are thought to be among the earliest forms of life on Earth. Jamie Carter, Forbes, 10 Oct. 2022 This supplement contains Lactobacillus acidophilus, which is a helpful microorganism that aids in digestion. The Salt Lake Tribune, 1 June 2022 Jezero Crater is on the western side of Isidis Planitia, a giant impact basin just north of the Martian equator that the authors also identified as being an ideal location to search for biosignatures of microorganism on Mars. Jamie Carter, Forbes, 10 Oct. 2022 That’s because the microorganism can lead to life-threatening illnesses in certain categories of people. Chris Smith, BGR, 23 Aug. 2022 Now, Formo’s focus is on scaling production at its microorganism dairies, bringing products to market by 2023, and, by 2030, replacing 10 percent of Europe’s dairy consumption. WIRED, 29 May 2022 With his observations of these fast, fat, and sundry-pawed creatures, Van Leeuwenhoek became the first person to ever see a microorganism—a discovery of almost incalculable significance to human health and our understanding of life on this planet. WIRED, 27 Sep. 2022 The Bay area's current bloom was formed by a microorganism called Heterosigma akashiwo. Wyatte Grantham-philips, USA TODAY, 1 Sep. 2022 This supplement includes Lactobacillus acidophilus, which is a beneficial microorganism that aids in digestion. The Salt Lake Tribune, 25 May 2022 See More

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.

Word History

Etymology

International Scientific Vocabulary

First Known Use

1880, in the meaning defined above

Time Traveler
The first known use of microorganism was in 1880

Dictionary Entries Near microorganism

Cite this Entry

“Microorganism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microorganism. Accessed 5 Dec. 2022.

Kids Definition

microorganism

noun

mi·​cro·​or·​gan·​ism ˌmī-krō-ˈȯr-gə-ˌniz-əm How to pronounce microorganism (audio)
: an organism (as a bacterium) of microscopic or less than microscopic size

Medical Definition

microorganism

noun

mi·​cro·​or·​gan·​ism -ˈȯr-gə-ˌniz-əm How to pronounce microorganism (audio)
: an organism of microscopic or ultramicroscopic size

More from Merriam-Webster on microorganism

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