Simple Definition of microorganism

from our Learner's Dictionary

microorganism

noun

ˌmaɪkroʊˈoɚgəˌnɪzəm

plural microorganisms

biology : an extremely small living thing that can only be seen with a microscope

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“Microorganism.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/microorganism. Accessed 22 Jun. 2026.

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Simple Definition of microorganism

microorganism

noun

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