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 delight in working with actors, fencers, acrobats, musicians and our creative team is infectious, and there is such pleasure in hearing his delicious language come alive and discovering what his world can become on stage. — Greg Evans, Deadline, 11 Oct. 2026 Since then, Sivitz’s hyperfixation has become infectious on X and beyond. — Maya Georgi, Rolling Stone, 10 Oct. 2026 Who could have imagined that an even more deadly infectious threat was literally right around the corner? — Robert C. Gallo, STAT, 9 Oct. 2026 Finally, pneumonic plague occurs when the bacterium infects the lungs—typically through inhalation of infectious droplets rather than flea bites. — Claire Maldarelli, Scientific American, 7 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

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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 21 Oct. 2026.

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