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

Around the planet, forces ranging from overfishing, pathogens from untreated sewage, fertilizer runoff, and the increasing challenge of global warming conspire to make things very difficult for coral reefs. David Grossman, Popular Mechanics, "New Atlas Captures Conditions of Nearly One-Fourth of World's Coral," 25 Apr. 2019 Parasites, pathogen, germs, those were a reliable source of disease and death in our ancestry. Rachel Becker, The Verge, "These 3D X-rays are spectacular and really gross," 14 Aug. 2018 If pathogens either initiate or accelerate Alzheimer’s, then classes of drugs that have never been considered for the disease should be in play. Sharon Begley, STAT, "New study supports long-dismissed idea: Herpes viruses could play role in Alzheimer’s," 21 June 2018 Some of these mats are manufactured with materials that appear to have some level of inherent anti-pathogen properties, like cork, while other brands claim to treat their mats with antimicrobial or antibacterial additives. Jessica Toscano, SELF, "Here's How Often You Should Really Clean Your Yoga Mat," 12 Apr. 2019 In Los Angeles, practitioners simply have to register with county officials, get a hepatitis B shot, and take a two-hour bloodborne-pathogens training course to start working as a semipermanent-makeup artist. Monica Corcoran Harel, Marie Claire, "What Is Cosmetic Tattooing? Read This Before You Get One," 29 Mar. 2019 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

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

6 Jun 2019

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Time Traveler for pathogen

The first known use of pathogen was in 1880

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More Definitions for pathogen



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

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