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.
But protections against infectious disease are continuing to falter, both domestically and abroad, through sheer neglect. Katherine J. Wu, The Atlantic, 21 May 2026 The Chicago Department of Public Health said that while the CDC Chicago Port Health Station at O'Hare conducts general infectious disease surveillance all the time, at the moment there is no enhanced screening being conducted for Ebola. Victor Jacobo, CBS News, 20 May 2026 At least one infectious disease expert agreed. Brenda Goodman, CNN Money, 20 May 2026 Many infectious disease experts are watching the current outbreak unfold with growing alarm. Gabrielle Emanuel, NPR, 20 May 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

Browse Nearby Words

Cite this Entry

“Infectious disease.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infectious%20disease. Accessed 23 May. 2026.

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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