microbiology

American  

[mahy-kroh-bahy-ol-uh-jee] / ˌmaɪ kroʊ baɪˈɒl ə dʒi /

noun

1. the branch of biology dealing with the structure, function, uses, and modes of existence of microscopic organisms.

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microbiology British  

/ ˌmaɪkrəʊˌbaɪəˈlɒdʒɪkəl, ˌmaɪkrəʊbaɪˈɒlədʒɪ /

noun

1. the branch of biology involving the study of microorganisms

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microbiology Scientific  

/ mī′krō-bī-ŏl′ə-jē /

1. The scientific study of microorganisms.

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Other Word Forms

• microbiologic
  adjective
• microbiological
  adjective
• microbiologically
  adverb
• microbiologist
  noun

Etymology

Origin of microbiology

First recorded in 1885–90; micro- + biology

Compare meaning

How does microbiology compare to similar and commonly confused words? Explore the most common comparisons:

• microbiology vs. biology

Explanation

Microbiology is the study of very small things, both living and nonliving. If you're fascinated by looking at tiny organisms through a microscope, you should take a class in microbiology. If your job involves microbiology, you're probably a microbiologist, a scientist who studies microorganisms and other microscopic things. Notice the prefix micro- in all of those words? It means "extremely small," from the Greek root mikros, "small or slight." Add this to biology, "the science of living things," and you get microbiology. This branch of science involves looking closely at fungi, viruses, parasites, bacteria, and other microbes.

Example Sentences

British Columbia health officer Bonnie Henry said the person's test came back as a presumptive positive on Friday, meaning that it still remains to be confirmed by a national microbiology lab.

From BBC • May 16, 2026

“These viruses are also what are called ‘low incidence, high consequences,’” said Robert Cross, a hantavirus researcher and assistant professor of microbiology and immunology at the University of Texas Medical Branch at Galveston.

From MarketWatch • May 7, 2026

Thermo Fisher TMO 0.07%increase; green up pointing triangle Scientific has struck a deal to sell its microbiology business to European private-equity firm Astorg for about $1.075 billion.

From The Wall Street Journal • Apr. 27, 2026

"Prior to selecting this combination of antibiotics, the surgical team did not consult with the hospital's microbiology team for advice."

From BBC • Mar. 11, 2026

The nutrients, while suitable for the comfortable environment of a university microbiology laboratory, were not designed for the arid polar wasteland.

From "Cosmos" by Carl Sagan