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 The spike in illnesses in children has been linked by Chinese health officials to known pathogens, according to the WHO. Adam Sabes, Fox News, 30 Nov. 2023 His team is currently conducting two other clinical trials to research wider applications for fighting drug-resistant pathogens. Popular Science, 1 Nov. 2023 Influence, it has been noted in this era of epidemics, shares a root word with influenza, an etymology that echoes the popular notion that ideas are free-floating pathogens that someone can catch without giving their conscious consent. Meghan O'Gieblyn, WIRED, 12 Oct. 2023 Conversely when your natural circadian rhythms are disrupted and sleep quality or duration starts to slip, too many inflammatory cytokines are triggered, resulting in elevated inflammation and an immune system that is compromised and ill equipped to deal with passing pathogens. Georgia Day, Vogue, 12 Oct. 2023 Why are the infectious doses of some pathogens higher or lower than those of others? Tara C. Smith, Quanta Magazine, 27 Sep. 2023 The Department of Transportation opened another investigation in 2023 over allegations that Neuralink was transporting antibiotic-resistant pathogens in an unsafe manner. Tori Otten, The New Republic, 22 Sep. 2023 These are the pillars of protection against infection from pretty much every pathogen. WIRED, 19 Nov. 2023 To date, the focus of research around South Bay sewage connected to the Tijuana River has been on the harmful pathogens such as E. coli, norovirus and salmonella that are regularly detected in freshwater that empties into the Pacific Ocean after crossing the border. Tammy Murga, San Diego Union-Tribune, 8 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'pathogen.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

Dictionary Entries Near pathogen

Cite this Entry

“Pathogen.” Dictionary, Merriam-Webster, Accessed 9 Dec. 2023.

Kids Definition


: a germ (as a bacterium or virus) that causes disease

Medical Definition


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

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