path·​o·​gen | \ ˈpa-thə-jən How to pronounce pathogen (audio) \

Definition of pathogen

: a specific causative agent (such as a bacterium or virus) of disease

Examples of pathogen in a Sentence

Recent Examples on the Web Since its inception, the CWA has instituted water quality standards for 150 different pollutants, such as toxic chemicals, nitrogen and pathogens. Lucia Walinchus,, "The water is cleaner but the politics are messier: The Clean Water Act movement after 50 years," 27 Dec. 2019 According to the Environmental Protection Agency, animal waste that decomposes in bodies of water releases nutrients and pathogens that causes excessive weed and algae growth. James Burky, The Denver Post, "From the lawn to the lab: Apartment complexes use DNA testing to keep bad dog owners in check," 7 Dec. 2019 Biomarkers to detect mild cognitive impairment earlier seemed promising, or therapies that target neurological inflammation or microbial pathogens. Katherine Ellen Foley, Quartz, "Science can’t fix dementia’s most heartbreaking problem," 2 Dec. 2019 Keep plants healthy with appropriate light exposure, watering schedule and temperature, and insects and pathogens are less likely to attack. oregonlive, "The key to healthy houseplants? Location, location, location," 11 Nov. 2019 Several landraces also possess resistance to pests and pathogens. Debal Deb, Scientific American, "The Struggle to Save Heirloom Rice in India," 16 Oct. 2019 Based on the limited evidence available, chemicals and microbial pathogens were a low concern for human health, the report said. Katie Hunt, CNN, "Microplastics in drinking water 'don't appear to pose health risk,' WHO says," 21 Aug. 2019 Nearly 50 other methods that were explored such as using contraceptives, individual traps, pathogens and others were deemed infeasible or unable to end the mouse problem for good. Will Houston, The Mercury News, "‘Like dropping a nuclear bomb on this island’: Feds delay Farallon Islands poison airdrop bid," 11 July 2019 Others assist her immune system in fending off the hordes of parasites and pathogens trying to invade her skin and other tissues. Quanta Magazine, "Should Evolution Treat Our Microbes as Part of Us?," 20 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pathogen.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of pathogen

1880, in the meaning defined above

History and Etymology for pathogen

patho- + -gen, after pathogenic, pathogenesis

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Time Traveler for pathogen

Time Traveler

The first known use of pathogen was in 1880

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Statistics for pathogen

Last Updated

17 Jan 2020

Cite this Entry

“Pathogen.” The Dictionary, Merriam-Webster Inc., Accessed 26 January 2020.

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More Definitions for pathogen


How to pronounce pathogen (audio)

English Language Learners Definition of pathogen

medical : something (such as a type of bacteria or a virus) that causes disease


patho·​gen | \ ˈpath-ə-jən How to pronounce pathogen (audio) \

Medical Definition of pathogen

: a specific causative agent (as a bacterium or virus) of disease

More from Merriam-Webster on pathogen

Britannica English: Translation of pathogen for Arabic Speakers Encyclopedia article about pathogen

Comments on pathogen

What made you want to look up pathogen? Please tell us where you read or heard it (including the quote, if possible).


to express in a more acceptable way

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