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 Crisscrossing the United States on an epic World Cup road trip, the pseudonymous soccer fan posted about the beauty of big-box chain stores and gas stations, projecting an infectious enthusiasm for American mass culture. — Will Oremus, The Atlantic, 1 July 2026 The atmosphere is infectious, attracting a discerning international crowd, yacht enthusiasts, fashion aficionados, and travelers who are seeking a blend of luxury and authenticity. — Condé Nast, Condé Nast Traveler, 5 July 2026 How To Safely Clean Up Mouse Droppings Mouse droppings can carry infectious bacteria and viruses like hantavirus, Salmonella, and leptospirosis. — Brandee Gruener, Southern Living, 1 July 2026 The songs on Night Ripper briefly imagine surreal all-star jams, like Elton John with Dave Grohl and Biggie Smalls, before one instantly recognizable sample drops out and is replaced by another, over and over with infectious momentum. — Al Shipley, SPIN, 29 June 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

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 7 Jul. 2026.

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More from Merriam-Webster on infectious

Nglish: Translation of infectious for Spanish Speakers

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