infectious

adjective

in-ˈfek-shəs How to pronounce infectious (audio)
Definition of infectiousnext
as in spreading
exciting a similar feeling or reaction in others an infectious giggle that got the whole class laughing

Synonyms & Similar Words

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Example Sentences

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.
Recent Examples of infectious His attention to detail and competitive spirit were infectious. — Larry Holder, New York Times, 4 Aug. 2026 And this is yet another example of Perez’s love for baseball, an infectious enthusiasm that endears him to fans. — Pete Grathoff, Kansas City Star, 4 Aug. 2026 Measles is highly contagious and is spread easily through the air when an infectious person breathes, coughs, or sneezes. — Michelle Richardson, CBS News, 4 Aug. 2026 Here’s what three infectious-disease doctors are preparing at home and ordering at restaurants during the outbreak, plus their thoughts on special health and safety considerations that might require some people to take extra precautions. — Emily Kay Votruba, EverydayHealth.com, 3 Aug. 2026 See All Example Sentences for infectious
Recent Examples of Synonyms for infectious
catching
Adjective
  • Instead, the Giants are making an even more shocking decision to ship Bailey, who will be eligible for arbitration for the first time this offseason, to the Guardians, who have their own crowded catching room between Bo Naylor and Austin Hedges.
    — Justice delos Santos, Mercury News, 9 May 2026
  • Christian Vázquez, who replaced Diaz in the lineup Monday, figures to take on primary catching duties while Diaz is out.
    — Matt Kawahara, Houston Chronicle, 4 May 2026
Definition of catching

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infection
infectious
infective
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Cite this Entry

“Infectious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/infectious. Accessed 14 Aug. 2026.

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More from Merriam-Webster on infectious

Nglish: Translation of infectious for Spanish Speakers

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