pathogen

American  

[path-uh-juhn, ‑-jen] / ˈpæθ ə dʒən, ‑ˌdʒɛn /

noun

1. any disease-producing agent, especially a virus, bacterium, or other microorganism.

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pathogen British  

/ ˈpæθəˌdʒiːn, ˈpæθəˌdʒɛn /

noun

1. any agent that can cause disease

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pathogen Scientific  

/ păth′ə-jən /

1. An agent that causes infection or disease, especially a microorganism, such as a bacterium or protozoan, or a virus.

2. See Note at germ

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pathogen Cultural  

1. A disease-causing agent. Microorganisms, viruses, and toxins are examples of pathogens.

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Other Word Forms

• antipathogen noun

Etymology

Origin of pathogen

First recorded in 1940–45; patho- + -gen

Example Sentences

"It expands the geographic frame for understanding how tuberculosis circulated in the past and highlights the value of integrating pathogen genomics into broader reconstructions of human history."

From Science Daily • Mar. 21, 2026

She added that the drugs did not provide effective coverage against a Gram-positive organism, which was the most likely pathogen causing the infection.

From BBC • Mar. 11, 2026

The team identified the T cell signals as cytokines that activate pathogen sensing receptors called toll-like receptors on innate immune cells.

From Science Daily • Feb. 23, 2026

We now have a much clearer picture of how humanity’s successes—population growth, food production, urbanization, globalization—have stoked pathogen evolution.

From The Wall Street Journal • Jan. 23, 2026

For practical purposes, the fact that feeding is interrupted promptly is of course an enormous advantage, for crop damage stops almost as soon as the pathogen is applied.

From "Silent Spring" by Rachel Carson

Related Words

• ailment
• disease
• germ
• illness
• infection
• microbe
• microorganism
• sickness