microorganism

American  

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

noun

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

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microorganism British  

/ ˌmaɪkrəʊˈɔːɡəˌnɪzəm /

noun

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

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microorganism Scientific  

/ mī′krō-ôr′gə-nĭz′əm /

1. 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.

2. See Note at germ

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Other Word Forms

• microorganic adjective
• microorganismal adjective

Etymology

Origin of microorganism

First recorded in 1875–80; micro- + organism

Example Sentences

“The presence of terrestrial microorganism within a sample of Ryugu underlines that microorganisms are the world's greatest colonizers and adept at circumventing contamination controls,” the authors conclude.

From Salon • Nov. 24, 2024

A growing number of studies have demonstrated the positive effects on the human immune system, moods and the microbiome, as the microorganism population of the body is known.

From Science Daily • Nov. 15, 2024

Mr. Gutman is the founder of Primer’s Yeast, a company that sells ancient strains of the microorganism.

From New York Times • Jun. 20, 2024

The microorganism also been connected to non-fatal, but sight-threatening, eye infections, sometimes through contaminated contact lens solution.

From Seattle Times • Mar. 13, 2024

And the same thing happens when a Venerian is attacked by an Earthly microorganism.

From Islands of Space by Campbell, John Wood

Related Words

• bacterium
• microbe
• pathogen
• virus