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

The patient said "it was like winning the lottery twice", added Myhre, who was also the lead author of a study describing the case in Nature Microbiology.

From Barron's • Apr. 13, 2026

This makes it difficult for authorities to design effective control measures, said Kritas, a professor of Microbiology and Infectious Diseases at Thessaloniki's Aristotelio University.

From Barron's • Mar. 30, 2026

Dr Sarah Hooper, a reader in Microbiology and Infection at the Cardiff School of Sport and Health Sciences, said a case as severe as Davies' isn't very common.

From BBC • Mar. 28, 2026

The group included scientists from the Max Planck Institute for Terrestrial Microbiology, the University of Ohio and the Philipps-University Marburg.

From Science Daily • Feb. 8, 2026

The debacle was no surprise to several of us who had just been in Oxford for a Society of General Microbiology meeting on “The Nature of Viral Multiplication.”

From "Double Helix" by James D. Watson