microorganism
noun
mi·cro·or·gan·ism
ˌmī-krō-ˈȯr-gə-ˌni-zəm 
: an organism (such as a bacterium or protozoan) of microscopic or ultramicroscopic size
Examples of microorganism in a Sentence
Recent Examples on the Web
Astronaut Butch Wilmore swabs the outside of the space station for microorganisms during Thursday's spacewalk.
—
Ashley Strickland, CNN, 30 Jan. 2025
The samples will be tested for signs of microorganisms on the outside of the space station.
—Josh Dinner, Space.com, 30 Jan. 2025
Biofilms are groups of microorganisms that stick to one another and, often, to surfaces.
—Sarah Kuta, Smithsonian Magazine, 27 Jan. 2025
And there would have been a simple way to directly confirm the presence of a concerning microorganism: Take stool cultures.
—Caity Weaver, New York Times, 25 Jan. 2025
See all Example Sentences for microorganism 
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Ashley Strickland, CNN, 30 Jan. 2025
The samples will be tested for signs of microorganisms on the outside of the space station.
—Josh Dinner, Space.com, 30 Jan. 2025
Biofilms are groups of microorganisms that stick to one another and, often, to surfaces.
—Sarah Kuta, Smithsonian Magazine, 27 Jan. 2025
And there would have been a simple way to directly confirm the presence of a concerning microorganism: Take stool cultures.
—Caity Weaver, New York Times, 25 Jan. 2025
See all Example Sentences for microorganism
Dictionary Entries Near microorganism
Cite this Entry
“Microorganism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microorganism. Accessed 7 Feb. 2025.
Copy CitationKids Definition
microorganism
noun
mi·cro·or·gan·ism
ˌmī-krō-ˈȯr-gə-ˌniz-əm
: 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
: an organism of microscopic or ultramicroscopic size
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