pathogen

noun

path·​o·​gen ˈpa-thə-jən 

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

Examples of pathogen in a Sentence

Recent Examples on the Web

Because the mRNA technology relies on a genetic plug-and-play model, in which different genetic sequences for any virus or pathogen can be switched into the vaccine, the shot takes around six weeks to develop. — Alice Park, Time, 6 Aug. 2026

Although salmonella and cyclospora are different pathogens, recent outbreaks have weighed on demand for some fresh produce and restaurant chains associated with those foods. — Aimee Picchi, CBS News, 4 Aug. 2026

Parents should understand that infectious pathogens like viruses and bacteria have not disappeared, but rather remain under control when vaccination rates stay high. — Omer Awan, Forbes.com, 2 Aug. 2026

These organisms, when introduced to other ecosystems, can cause a wide array of consequences, from outcompeting native species to damaging infrastructure to introducing pathogens harmful to marine life and, sometimes, humans. — Christopher Cann, USA Today, 2 Aug. 2026

Word History

Etymology

patho- + -gen, after pathogenic, pathogenesis

First Known Use

1880, in the meaning defined above

Kids Definition

pathogen

noun

patho·​gen

ˈpath-ə-jən

: a germ (as a bacterium or virus) that causes disease

Medical Definition

pathogen

noun

patho·​gen ˈpath-ə-jən 

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