microorganism [mahy-kroh- awr-g uh-niz- uh m] noun any organism too small to be viewed by the unaided eye, as bacteria, protozoa, and some fungi and algae. Related forms mi·cro·or·gan·ic , [mahy-kroh-awr- gan-ik] /ˌmaɪ kroʊ ɔrˈgæn ɪk/ mi·cro·or·gan·is·mal, adjective
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for microorganism Historical Examples of microorganism British Dictionary definitions for microorganism noun any organism, such as a bacterium, protozoan, or virus, of microscopic size
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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microorganism in Medicine microorganism [mī′krō-ôr ′gə-nĭz′əm] n. An organism of microscopic or submicroscopic size, especially a bacterium or protozoan.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
An organism that can be seen only with the aid of a microscope and that typically consists of only a single cell. Microorganisms include bacteria, protozoans, and certain algae and fungi. See Note at germ.
The American Heritage® Science Dictionary
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