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
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Modern water treatment solutions can significantly reduce nutrient loads, pathogens and harmful contaminants before wastewater ever reaches the ocean.
—
Steve Adelstein, The Orlando Sentinel, 27 Mar. 2026
The oldest approach to vaccination in use today includes either inactivated pathogens—such as those in most modern polio vaccines—or pathogens that remain viable but have been weakened enough not to trigger disease—such as those in the measles, mumps and rubella, or MMR, vaccine.
—Meghan Bartels, Scientific American, 27 Mar. 2026
Most soil bacteria aren't human pathogens.
—Jonathan Lambert, NPR, 27 Mar. 2026
The ticks were then tested for five human disease-causing pathogens including anaplasmosis, babesiosis, Lyme disease, hard tick relapsing fever and Powassan virus.
—Stephen Underwood, Hartford Courant, 25 Mar. 2026
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Steve Adelstein, The Orlando Sentinel, 27 Mar. 2026
The oldest approach to vaccination in use today includes either inactivated pathogens—such as those in most modern polio vaccines—or pathogens that remain viable but have been weakened enough not to trigger disease—such as those in the measles, mumps and rubella, or MMR, vaccine.
—Meghan Bartels, Scientific American, 27 Mar. 2026
Most soil bacteria aren't human pathogens.
—Jonathan Lambert, NPR, 27 Mar. 2026
The ticks were then tested for five human disease-causing pathogens including anaplasmosis, babesiosis, Lyme disease, hard tick relapsing fever and Powassan virus.
—Stephen Underwood, Hartford Courant, 25 Mar. 2026
See All Example Sentences for pathogen
Cite this Entry
“Pathogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pathogen. Accessed 1 Apr. 2026.
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pathogen
noun
patho·gen
ˈpath-ə-jən
: a specific causative agent (as a bacterium or virus) of disease
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