pathogen

noun

path·​o·​gen ˈpa-thə-jən How to pronounce pathogen (audio)
: a specific causative agent (such as a bacterium or virus) of disease

Examples of pathogen in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Tech giants have told us all about how AI will take control away from society, steal our jobs, allow bad actors to design dangerous pathogens or cause a catastrophic cyberattack or destroy our financial systems. — Staff, FOXNews.com, 23 Oct. 2026 Mechanical vectors passively pass infectious agents from one host or surface to another; the pathogen does not develop or replicate inside the vector. — Encyclopedia Britannica, 23 Oct. 2026 Better vaccines can keep outbreaks from destroying herds and flocks, protect food production, and reduce opportunities for pathogens to spread to people. — Robert Kelly, Fortune, 22 Oct. 2026 Cleveland Clinic notes that many experts view it as a colonizer or bystander rather than an active pathogen. — Hanna Wickes, Charlotte Observer, 19 Oct. 2026 See All Example Sentences for pathogen

Word History

Etymology

patho- + -gen, after pathogenic, pathogenesis

First Known Use

1880, in the meaning defined above

Time Traveler
The first known use of pathogen was in 1880

Browse Nearby Words

path of emergence
pathogen
pathogenesis
See all Nearby Words

Cite this Entry

“Pathogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pathogen. Accessed 27 Oct. 2026.

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Kids Definition

pathogen

noun
patho·​gen
ˈpath-ə-jən
: a germ (as a bacterium or virus) that causes disease

Medical Definition

pathogen

noun
patho·​gen ˈpath-ə-jən How to pronounce pathogen (audio)
: a specific causative agent (as a bacterium or virus) of disease

More from Merriam-Webster on pathogen

Britannica.com: Encyclopedia article about pathogen

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