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

Freezing doesn’t kill pathogens and the alcohol in a drink won’t either, so ice made from tap water stays risky. — Ryan Brennan, Miami Herald, 24 June 2026

Why these trade-offs matter Our findings show that the effects of pathogens go beyond immediate death. — Ana V. Longo, The Conversation, 24 June 2026

While critical to our entire ecosystem, habitat loss, pesticides, pathogens, and changes in land use among other impacts threaten the pollinators. — Laura Baisas, Popular Science, 24 June 2026

Western black-legged ticks, which are found mostly on the Pacific coast, also carry Lyme bacteria, as well as several other pathogens, but typically less than 5 percent of them are infected, according to TickEncounter. — Kate Wong, Scientific American, 22 June 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