microorganism

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

Definition of microorganism

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

Origin and Etymology of microorganism

International Scientific Vocabulary


First Known Use: 1880


MICROORGANISM Defined for English Language Learners

microorganism

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

Definition of microorganism for English Language Learners

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


MICROORGANISM Defined for Kids

microorganism

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

Definition of microorganism for Students

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


Medical Dictionary

microorganism

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

Medical Definition of microorganism

  1. :  an organism of microscopic or ultramicroscopic size



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