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 Another infectious traveler passed through LAX while infected with measles earlier this month. — Los Angeles Times, 23 July 2026 Direct person-to-person transmission is unlikely, according to the CDC, because the parasite outside a human body takes one to two weeks to become infectious. — Mateo Rosiles, USA Today, 21 July 2026 The White House remains underprepared to manage infectious threats. — David Blumenthal, STAT, 20 July 2026 In Orange County, the Florida Department of Health in Orange County maintains infectious-disease surveillance and disease-reporting services for residents and visitors, which is exactly how local systems stay ready without alarming the public. — Luis E. Caso Vega, The Orlando Sentinel, 18 July 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 4 Aug. 2026.

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More from Merriam-Webster on infectious

Nglish: Translation of infectious for Spanish Speakers

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