Definition of microorganism
: an organism (such as a bacterium or protozoan) of microscopic or ultramicroscopic size
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Origin and Etymology of microorganism
International Scientific Vocabulary
First Known Use: 1880
MICROORGANISM Defined for English Language Learners
microorganism
playDefinition of microorganism for English Language Learners
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biology : an extremely small living thing that can only be seen with a microscope
MICROORGANISM Defined for Kids
microorganism
playDefinition of microorganism for Students
: a living thing (as a bacterium) that can only be seen with a microscope
Medical Dictionary
microorganism
playMedical Definition of microorganism
: an organism of microscopic or ultramicroscopic size
Learn More about microorganism
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Spanish Central: Translation of microorganism Nglish: Translation of microorganism for Spanish speakers Britannica.com: Encyclopedia article about microorganism
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