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.
Harrison added that the recall has nothing to do with an allergen, microorganism or pathogen contamination. — Saleen Martin, USA Today, 31 Aug. 2026 One of the most devestating aspects of modern medicine and drug development is the constantly evolving nature of harmful pathogens and bacteria. — Dr. Sai Balasubramanian, Forbes.com, 30 Aug. 2026 Although the pathogen has been detected in Arizona, official reports have yet to find a single bat death here so far. — Shi En Kim, AZCentral.com, 28 Aug. 2026 And the planet continues to warm, allowing these pathogens to spread to more and more farms all over the world, including in the US. — Dylan Scott, Vox, 27 Aug. 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 4 Sep. 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

Last Updated: - Updated example sentences
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