infectious disease

noun

: a disease (such as influenza, malaria, meningitis, rabies, or tetanus) caused by the entrance into the body of pathogenic agents or microorganisms (such as bacteria, viruses, protozoans, or fungi) which grow and multiply there compare communicable disease, contagious disease

Examples of infectious disease in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Most doctors, public health authorities and infectious disease experts strongly dispute that, arguing that vaccines are very safe and highly effective. — Rob Stein, NPR, 2 Sep. 2026 If different agencies use different language and terminology to explain infectious disease deaths without explaining why, the public is left to fill in the gaps. — Omer Awan, Forbes.com, 30 Aug. 2026 However, Boise school officials are well versed in infectious disease trends. — Hali Smith, Idaho Statesman, 28 Aug. 2026 Pediatric infectious disease experts said hospitals almost never restrict a parent’s access to their child’s bedside. — Brenda Goodman, CNN Money, 28 Aug. 2026 See All Example Sentences for infectious disease

Word History

First Known Use

1600, in the meaning defined above

Time Traveler
The first known use of infectious disease was in 1600

Rhymes for infectious disease

See All Rhymes for infectious disease

Browse Nearby Words

infectious chlorosis
infectious disease
infectious ectromelia
See all Nearby Words

Cite this Entry

“Infectious disease.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infectious%20disease. Accessed 4 Sep. 2026.

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Kids Definition

infectious disease

noun
: a disease caused by the presence, growth, and increase in numbers of germs in the body

Medical Definition

infectious disease

noun
: a disease (as influenza, malaria, meningitis, rabies, or tetanus) caused by the entrance into the body of pathogenic agents or microorganisms (as bacteria, viruses, protozoans, or fungi) which grow and multiply there compare communicable disease, contagious disease
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