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
May Improve Gut Health The gut microbiota is a mix of microorganisms (tiny living things, including bacteria) that play a role in many body functions, such as the immune system and metabolism.
—
Karen Berger, Pharmd, Verywell Health, 11 Apr. 2025
While intestines may have lots of friendly microorganisms, intestines can have pathogens too.
—Bruce Y. Lee, Forbes.com, 11 Apr. 2025
Cats with inflammatory bowel disease might need a prescription-strength probiotic supplement with higher amounts of microorganisms.
—Bestreviews, Chicago Tribune, 4 Apr. 2025
This helps to ensure that the dishes are fully cleaned and that any microorganisms, like bacteria or viruses, are eliminated.
—Timothy Dale, Better Homes & Gardens, 1 Mar. 2025
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Karen Berger, Pharmd, Verywell Health, 11 Apr. 2025
While intestines may have lots of friendly microorganisms, intestines can have pathogens too.
—Bruce Y. Lee, Forbes.com, 11 Apr. 2025
Cats with inflammatory bowel disease might need a prescription-strength probiotic supplement with higher amounts of microorganisms.
—Bestreviews, Chicago Tribune, 4 Apr. 2025
This helps to ensure that the dishes are fully cleaned and that any microorganisms, like bacteria or viruses, are eliminated.
—Timothy Dale, Better Homes & Gardens, 1 Mar. 2025
See All Example Sentences for microorganism
Cite this Entry
“Microorganism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microorganism. Accessed 23 Apr. 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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