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
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Under blue light, the microorganisms cluster together and migrate toward the liquid-air interface, forming dense swarms.
—
Neetika Walter, Interesting Engineering, 15 May 2026
Kefir Has More Diverse Probiotics Probiotics are living microorganisms that support gut health.
—Merve Ceylan, Health, 15 May 2026
According to The University of Texas MD Anderson Cancer Center, different prebiotic foods feed different types of microorganisms, while different probiotic foods introduce different bacterial strains.
—Ryan Brennan, Fort Worth Star-Telegram, 15 May 2026
According to The University of Texas MD Anderson Cancer Center, different prebiotic foods feed different microorganisms, while different probiotic foods introduce different bacterial strains.
—Ryan Brennan, Sacbee.com, 15 May 2026
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Neetika Walter, Interesting Engineering, 15 May 2026
Kefir Has More Diverse Probiotics Probiotics are living microorganisms that support gut health.
—Merve Ceylan, Health, 15 May 2026
According to The University of Texas MD Anderson Cancer Center, different prebiotic foods feed different types of microorganisms, while different probiotic foods introduce different bacterial strains.
—Ryan Brennan, Fort Worth Star-Telegram, 15 May 2026
According to The University of Texas MD Anderson Cancer Center, different prebiotic foods feed different microorganisms, while different probiotic foods introduce different bacterial strains.
—Ryan Brennan, Sacbee.com, 15 May 2026
See All Example Sentences for microorganism
Cite this Entry
“Microorganism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microorganism. Accessed 21 May. 2026.
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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