infection

noun

Definition of infectionnext
as in virus
an abnormal state caused by contact with harmful organisms (such as bacteria or viruses) There is a viral infection spreading among the schoolchildren.

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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 infection Severe or repeated infections may leave scars that can permanently reduce kidney function. — Md Published, Verywell Health, 23 Oct. 2026 Pathogens and mechanisms of infection Different pathogens rely on different forms of transmission. — Encyclopedia Britannica, 23 Oct. 2026 These animals would be crowded together, each infection raising the odds that a new strain could arise through mutation. — Nat Lash, ProPublica, 23 Oct. 2026 Most people think of vaccines as preventing an infection, like measles or whooping cough. — ABC News, 22 Oct. 2026 See All Example Sentences for infection
Recent Examples of Synonyms for infection
  1. virus
  2. germ
Noun
  • Only in this case, the vaccine’s mRNA teaches immune cells to recognize key features of an individual’s cancer rather than a virus.
    — Mike McRae October 25, New Atlas, 26 Oct. 2026
  • Many of us were still continuing with our lives, following the virus on the margins.
    — Amanda Erickson, STAT, 26 Oct. 2026
Definition of virus
Noun
  • In the very early days of COVID-19, millions who'd rarely thought twice about germ avoidance became germophobes.
    — Jonathan Lambert, NPR, 23 Oct. 2026
  • These germs can make people sick with an illness called salmonellosis.
    — Sacbee.com, Sacbee.com, 21 Oct. 2026
Definition of germ

Browse Nearby Words

infecting
infection
infectious
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Cite this Entry

“Infection.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/infection. Accessed 29 Oct. 2026.

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More from Merriam-Webster on infection

Britannica.com: Encyclopedia article about infection

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