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.

---

microorganism British  

/ ˌmaɪkrəʊˈɔːɡəˌnɪzəm /

noun

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

---

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

---

Other Word Forms

• microorganic adjective
• microorganismal adjective

Etymology

Origin of microorganism

First recorded in 1875–80; micro- + organism

Example Sentences

"This work highlights a new way environmental change can affect marine ecosystems, not simply by limiting resources, but by disrupting the internal physiology of dominant microorganisms," Cheng said.

From Science Daily

Some trials show that the sweeteners can raise blood sugar, weaken blood-sugar control and cause dysfunction in the gut microbiome, the collection of bacteria and other microorganisms in the gut.

From The Wall Street Journal

The familiar chewy texture and tangy flavor of sourdough come from a complex mix of microorganisms that ferment the dough.

From Science Daily

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

Related Words

• bacterium
• microbe
• pathogen
• virus