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Synonyms

microbe

American  
[mahy-krohb] / ˈmaɪ kroʊb /

noun

  1. a microorganism, especially a pathogenic bacterium.


microbe British  
/ ˈmaɪkrəʊb /

noun

  1. any microscopic organism, esp a disease-causing bacterium

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

microbe Scientific  
/ mīkrōb′ /
  1. A microorganism, especially a bacterium that causes disease.

  2. See Note at germ


Other Word Forms

  • microbeless adjective
  • microbial adjective
  • microbian adjective
  • microbic adjective
  • nonmicrobic adjective
  • unmicrobial adjective
  • unmicrobic adjective

Etymology

Origin of microbe

1880–85; < French < Greek mīkro- micro- + bíos life

Explanation

Microbe is a somewhat outdated way for scientists to talk about the tiny bugs that cause diseases. When you get the flu, you can blame a microbe. In the nineteenth century, the idea that germs caused illness was brand new, and doctors referred to both germs and microbes interchangeably. The word microorganism is more scientifically precise, and in fact microbe is a shortened form of that long, Greek-rooted word. Mikro means "small," and in microbe it's combined with bios, or "life."

Keep Reading on Vocabulary.com

Vocabulary lists containing microbe

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Published in Cell Communication and Signaling, the study focuses on Fusobacterium nucleatum, a microbe previously connected to colorectal and other cancers.

From Science Daily • Mar. 19, 2026

But new research suggests that a key marine microbe, Nitrosopumilus maritimus, may already be adjusting to warmer and more nutrient-poor conditions.

From Science Daily • Mar. 11, 2026

Their findings show that at least one microbe can tolerate ambiguity in its genetic code, overturning a central assumption in biology.

From Science Daily • Feb. 28, 2026

One previous piece of research on Neanderthal DNA also showed that modern humans and Neanderthals shared an oral microbe - a type of bacteria found in our saliva.

From BBC • Nov. 18, 2025

That seems especially puzzling and self-defeating, since a microbe that kills its host kills itself.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond