microorganism

[ mahy-kroh-awr-guh-niz-uhm ]

noun

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

microorganism

/ ˌmaɪkrəʊˈɔːɡəˌnɪzəm /

noun

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

microorganism

/ 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 Words From

• mi·cro·or·gan·ic [mahy-kroh-awr-, gan, -ik], micro·organ·ismal adjective

Word History and Origins

Origin of microorganism¹

First recorded in 1875–80; micro- + organism

Example Sentences

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

From New York Times

Infection occurs when a virus, bacteria, or other disease-causing microorganism enters a human’s body and begin to multiply.

From National Geographic Kids

"Essentially, one of the tools we developed leverages the structure of this graph in order to determine which pieces of DNA appear repeatedly either across microbes or within the same microorganism."

From Science Daily

The study of the variability of microorganism populations has been possible thanks to the large-scale application of molecular techniques such as metagenomics and metatranscriptomics, which have revolutionized the ability to analyze these populations directly from their habitats, overcoming some of the limitations of traditional laboratory culture methods.

From Science Daily

Infection occurs when a virus, bacteria, or other disease-causing microorganism enters a human’s body and begin to multiply.

From National Geographic Kids

Related Words

• bacterium
• microbe
• pathogen
• virus