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

Because they function at the same scale as many living microorganisms, the robots could one day help doctors monitor individual cells or assist engineers in assembling tiny devices used in advanced manufacturing.

From Science Daily

Life on Earth began with simple microorganisms in shallow water environments.

From Science Daily

The nutrient must first be converted into a usable form through a process called nitrogen fixation, which relies on microorganisms in the soil.

From Science Daily

Their work highlights the important ways microbes can support human health, challenging the idea that all microorganisms are threats.

From Science Daily

The gut microbiome consists of trillions of microorganisms living in the digestive tract, where they play important roles in digestion and overall health.

From Science Daily

Related Words

• bacterium
• microbe
• pathogen
• virus