Dictionary

microorganism

noun mi·cro·or·gan·ism \-ˈȯr-gə-ˌni-zəm\

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

Full Definition of MICROORGANISM

: an organism (as a bacterium or protozoan) of microscopic or ultramicroscopic size

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International Scientific Vocabulary

First Known Use: 1880

MICROORGANISM Defined for Kids

noun mi·cro·or·gan·ism \ˌmī-krō-ˈȯr-gə-ˌni-zəm\

: a living thing (as a bacterium) that can only be seen with a microscope

Medical Dictionary

noun mi·cro·or·gan·ism \-ˈȯr-gə-ˌniz-əm\

: an organism of microscopic or ultramicroscopic size

Next Word in the Dictionary: micropaleontologyPrevious Word in the Dictionary: micronutrientAll Words Near: microorganism

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