path·​o·​gen | \ ˈpa-thə-jən \

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

These pathogens, which affect mostly horses and dogs, can enter an animal's body through small cuts or abrasions. Kelly O'sullivan, Country Living, "A Deadly 'Swamp Cancer' Has Killed Seven of the Famous Chincoteague Wild Ponies," 11 Jan. 2019 Eggs aren't the only reason to avoid eating raw dough or batter—flour can carry pathogens, too. Sarah Jacoby, SELF, "General Mills Recalls Gold Medal Flour for Possible Salmonella Risk," 24 Jan. 2019 Note: 2018 data as of December 7 Source: Centers for Disease Control and Prevention A key tool in the fight against foodborne illness, whole genome sequencing, is used to map the complete DNA of a pathogen. Jesse Newman, WSJ, "Foodborne Illness Outbreaks in Spotlight as Technology Improves," 18 Dec. 2018 Hepatitis B is a pathogen that causes a liver infection, the CDC explains. Jessica Toscano, SELF, "9 Smart Questions to Ask Before Getting a Tattoo," 9 Nov. 2018 According to the US National Library of Medicine, Capnocytophaga Canimorsus is a bacterial pathogen that is most commonly found in the saliva of healthy dogs and cats. Elly Belle, Teen Vogue, "A Man Reportedly Had His Hands and Legs Amputated Because of an Infection Caused By a Dog Lick," 1 Aug. 2018 These groups are often advised by their doctors to avoid eating foods that may contain pathogens anyway. Jim Prevor, WSJ, "Lettuce Try Not to Panic," 29 Nov. 2018 All these animals produce feces and urine, which can contain pathogens and dangerous chemicals. Umair Irfan, Vox, "Florence dropped so much rain that hog waste is spilling out of lagoons," 18 Sep. 2018 Now, a pair of new genetic studies suggests the pathogen has been with us at least since the dawn of civilization. Michael Price, Science | AAAS, "Liver-destroying virus may have been with us since the dawn of civilization," 9 May 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

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Last Updated

14 Feb 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 \

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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