microorganism

[ mahy-kroh-awr-guh-niz-uh m ]
/ ˌmaɪ kroʊˈɔr gəˌnɪz əm /

noun

any organism too small to be viewed by the unaided eye, as bacteria, protozoa, and some fungi and algae.

Origin of microorganism

First recorded in 1875–80; micro- + organism

OTHER WORDS FROM microorganism

mi·cro·or·gan·ic [mahy-kroh-awr-gan-ik] /ˌmaɪ kroʊ ɔrˈgæn ɪk/, mi·cro·or·gan·is·mal, adjective

Example sentences from the Web for microorganism

British Dictionary definitions for microorganism

microorganism
/ (ˌmaɪkrəʊˈɔːɡəˌnɪzəm) /

noun

any organism, such as a bacterium, protozoan, or virus, of microscopic size

Medical definitions for microorganism

microorganism
[ mī′krō-ôrgə-nĭz′əm ]

n.

An organism of microscopic or submicroscopic size, especially a bacterium or protozoan.

Scientific definitions for microorganism

microorganism
[ mī′krō-ôrgə-nĭz′əm ]

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.