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germ theory

American  

noun

  1. Pathology. the theory that infectious diseases are due to the agency of germs or microorganisms.

  2. Biology. biogenesis.


germ theory British  

noun

  1. the theory that all infectious diseases are caused by microorganisms

  2. the theory that living organisms develop from other living organisms by the growth and differentiation of germ cells

"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

Etymology

Origin of germ theory

First recorded in 1870–75

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.

See Examples For:

The author appreciates what a terrific advance modern germ theory represents, but she also recognizes its tendency to generate absurd excesses.

From The Wall Street Journal Jan. 23, 2026

He doesn't entirely believe in germ theory, suggesting that a "healthy" human body cannot be damaged by microbes.

From Salon Jan. 27, 2025

Dominique Janee: This was before doctors knew much about germ theory of disease.

From Scientific American Nov. 2, 2023

Crowded conditions in the mission dorms, and the lack of understanding of germ theory at the time, led to “incredible mortality,” Hackel says.

From Los Angeles Times Jun. 28, 2023

Pasteur's "germ theory" will lead to a revolution in medicine.

From "Phineas Gage" by John Fleischman

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