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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Microbe is a somewhat outdated way for scientists to talk about the tiny bugs that cause diseases.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.

The microbe, Methanosarcina acetivorans, appears to function normally despite this flexible interpretation, demonstrating that life can operate with a slightly imprecise code.

From Science Daily • Feb. 28, 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

Among them is one unusual microbe that produces methane -- a gas more often associated with cows and landfills than humans.

From Science Daily • Oct. 24, 2025

What evolutionary benefit does a microbe derive from making us sick in bizarre ways, like giving us genital sores or diarrhea?

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