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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:

UK holidaymakers are being warned about a nasty infectious disease called cyclosporiasis that can cause explosive diarrhoea, after a sharp rise in cases.

From BBC Jul. 30, 2026

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

There are constant outbreaks of infectious disease on these floating holidays, and people want to know whether I would tolerate the risk of getting ill on a cruise ship.

From Slate May 16, 2026

Europeans may not have known about microbes, but they thoroughly understood infectious disease.

From "1491" by Charles C. Mann

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