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.
Antimicrobials include antibiotics, antivirals, antifungals, and antiparasitics—all used to prevent and treat infectious disease. Hannah Millington, MSNBC Newsweek, 14 Oct. 2025 Vaccination is the most effective way to prevent the spread of measles, which is the most infectious disease known to humans. Rob Williams, EverydayHealth.com, 13 Oct. 2025 Deaths worldwide have generally been shifting away from infectious disease, with sharp declines in deaths from measles, diarrheal diseases and tuberculosis, according to IHME. Deidre McPhillips, CNN Money, 12 Oct. 2025 Multiple sources familiar with the matter told news outlets including The New York Times and Washington Post that those who were notified of layoffs Friday included people on teams on infectious disease outbreaks, science and health data analysis and employee safety. The Hill, 12 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Infectious disease.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infectious%20disease. Accessed 22 Oct. 2025.

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
Last Updated: - Updated example sentences
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