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Microbe is a somewhat outdated way for scientists to talk about the tiny bugs that cause diseases.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

Scientists believe additional gene microbe links likely exist, but proving them is difficult because genetic and environmental factors overlap in everyday life.

From Science Daily • Dec. 23, 2025

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

By linking the cell's survival to the production of their target compound, the team was able to trick the microbe into creating xanthommatin.

From Science Daily • Nov. 3, 2025

For a microbe, spread may be defined mathematically as the number of new victims infected per each original patient.

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