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

Photo: Jesse Newman/The Wall Street Journal Several peers operate digesters that reduce pathogens in manure and produce methane that can be burned to produce electricity. Jesse Newman And Patrick Mcgroarty, WSJ, "Farms, More Productive Than Ever, Are Poisoning Drinking Water in Rural America," 18 Jan. 2019 The bacteria that succeed as pathogens tend to be generalists, capable of surviving either in a host or in the hospitable environment outside a host’s body. Kiona N. Smith, Ars Technica, "Mammals inherit most of their gut bacteria, new study suggests," 26 Oct. 2018 The board has been testing water samples weekly along the river this summer in an effort to pinpoint problem areas, look for pathogens and determine the sources of contamination. Cynthia Hubert, sacbee, "Heading to the American River this week? Here's where E. coli levels are high," 3 July 2018 Together, the oils produced by your skin keep the layers of your skin soft, seal hydration in, and protect against allergens and pathogens by keeping the stratum corneum in tact. Jenn Sinrich, SELF, "What You Should Know Before Using a Trendy New Face Oil," 13 Mar. 2019 When pathogens and pests are caught quickly, destruction can be significantly curtailed. Henry Robertson, Popular Mechanics, "An App Could Be the Key to Saving Crops from Pests and Pathogens," 4 Dec. 2018 Other pathogens facing similar challenges tend to evolve smaller genomes and greater virulence. Kiona N. Smith, Ars Technica, "Ancient DNA reveals the secrets of a devastating European disease," 26 Sep. 2018 Native Americans’ downfall, Dr. Crosby said, was not so much the superior technologies or fighting prowess of the conquistadors but the smallpox and other pathogens that Spaniards unwittingly carried on their ships. Harrison Smith, Washington Post, "Alfred Crosby, environmental historian of ‘Columbian exchange,’ dies at 87," 5 Apr. 2018 Bacteria, viruses and other pathogens are small, with rapid reproductive rates compared to those of human beings. David P. Barash, WSJ, "‘Good Reasons for Bad Feelings’ Review: Suffering’s Silver Lining," 13 Feb. 2019

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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Statistics for pathogen

Last Updated

23 Apr 2019

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Time Traveler for pathogen

The first known use of pathogen was in 1880

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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 move or proceed with twists and turns

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