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 Out of 163 cases, 126 patients have been tested for adenovirus, and 91, or 72% were positive for that pathogen. Brenda Goodman, CNN, 6 May 2022 The work of watching changes to the virus functions as a kind of early warning system, said David Engelthaler, director of the pathogen and microbiome division at TGen. Melina Walling, The Arizona Republic, 6 May 2022 One is by teaching T-cells to recognize and kill the pathogen. Angus Chen, STAT, 14 Apr. 2022 What to know about the viral pathogen To examine possible viruses, researchers analyzed 35,000 water samples taken from all oceans throughout the world. Jordan Mendoza, USA TODAY, 11 Apr. 2022 The theory is that the canine virus will multiply for a limited time in people’s noses, teaching their immune systems to recognize the coronavirus spike protein and block the real pathogen. Carolyn Y. Johnson, Anchorage Daily News, 11 Apr. 2022 If the pathogen continues to spread, entomologists behind the study say the fungus could make a serious dent in the U.S. crazy ant population within the next few years. Corryn Wetzel, Smithsonian Magazine, 1 Apr. 2022 The scale of the program is unparalleled in Beijing, even as China has kept COVID in check since early 2020 thanks in large part to massive testing efforts that repeatedly spotted tiny incursions of the pathogen in the world’s most populous country. Time, 26 Apr. 2022 That could be especially dangerous if the country is dealing with a new variant or a new pathogen that spreads to new areas via interstate travel. Rachel Gutman, The Atlantic, 20 Apr. 2022 See More

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.

First Known Use of pathogen

1880, in the meaning defined above

History and Etymology for pathogen

patho- + -gen, after pathogenic, pathogenesis

Learn More About pathogen

Time Traveler for pathogen

Time Traveler

The first known use of pathogen was in 1880

See more words from the same year

Dictionary Entries Near pathogen

path of emergence



See More Nearby Entries 

Statistics for pathogen

Last Updated

17 May 2022

Cite this Entry

“Pathogen.” Dictionary, Merriam-Webster, Accessed 24 May. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

More Definitions for pathogen


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


Test Your Vocabulary

Great Words for Scrabble

  • scrabble tiles that read scrabble quiz
  • Which of the following Q-without-U words means the number five in cards or dice?
True or False

Test your knowledge - and maybe learn something along the way.

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!