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infectious disease

American  
[in-fek-shuhs di-zeez] / ɪnˈfɛk ʃəs dɪˈziz /

noun

  1. a disease caused by a bacterium, virus, or other microorganism, and often spreading by contact between individuals or by a vector such as an insect: ID

    Chicken pox and cholera are infectious diseases.


infectious disease Scientific  
  1. A disease caused by a microorganism or other agent, such as a bacterium, fungus, or virus, that enters the body of an organism.


Etymology

Origin of infectious disease

First recorded in 1570–80

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Dr. Trahern W. Jones, a pediatric infectious disease specialist in Utah, said the outbreak was no accident: “This outbreak is the product of years of miscommunication and misinformation.”

From The Wall Street Journal Jun. 13, 2026

Other than measles, which is preventable, the U.S. is not the center of any major infectious disease outbreaks.

From Salon May 20, 2026

If you’ve got a cruise booked, it’s perhaps worth thinking about how you might reduce your risk of infectious disease.

From Slate May 16, 2026

Public health and infectious disease specialists will assess whether the individuals are able to self-isolate at home, or whether another location should be arranged.

From BBC May 13, 2026

It’s a vast congregation of hunger, infectious disease, and desperation, masquerading as opportunity.

From "The Poisonwood Bible" by Barbara Kingsolver

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