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 Roivant and its spinout Priovant said Wednesday that their immune-modifying pill Lisraya was more effective than placebo in treating the inflammatory eye disease non-infectious uveitis. — Jason Mast, STAT, 21 Oct. 2026 The American Academy of Dermatology echoes those concerns, warning that cosmetic tattooing can lead to complications including allergic and infectious reactions. — Ashley Lynch, Miami Herald, 21 Oct. 2026 And the rest of us need her infectious smile and unmistakable laugh back in our lives. — Meghan O'Brien, NBC news, 19 Oct. 2026 The necropsy found that Jackie had multiple conditions, including a type of infectious avian flu. — ABC News, 15 Oct. 2026 See All Example Sentences for infectious
Recent Examples of Synonyms for infectious
catching
Adjective
  • The Sox need starting pitching and bullpen help, more contact hitters, a stronger bench and yes, more catching, as Teel and Edgar Quero both regressed.
    — Paul Sullivan, Chicago Tribune, 13 Oct. 2026
  • 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
Definition of catching

Browse Nearby Words

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 28 Oct. 2026.

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