infection

noun

in·​fec·​tion in-ˈfek-shən How to pronounce infection (audio)
Synonyms of infectionnext
1
a
: the state produced by the establishment of one or more pathogenic agents (such as a bacteria, protozoans, or viruses) in or on the body of a suitable host
an infection in his foot
b
: a disease resulting from infection
contagious infections
infections of childhood
2
: an act or process of infecting something or someone
also : the establishment of a pathogen in its host after invasion
3
: an infectious agent or material contaminated with an infectious agent
… that notion that the infection was all in the air, that there was no such thing as contagion from the sick people to the sound …—Daniel Defoe
It may not be uninteresting to add, that this case I vaccinated with infection taken from a secondary pock on the arm of her sister …—John Redman Coxe
4
: the communication of emotions or qualities through example or contact
But immediately she resisted this intolerable fear as an infection from her husband's way of thinking.—George Eliot
also : the emotion or quality that is communicated
… as the evening wore on, she caught the infection of their excitement … —Thomas Hardy
Besides, I know what sort of a mind I have placed in communication with my own: I know it is one not liable to take infection … —Charlotte Brontë
5
: the act or result of corrupting someone's morals, character, etc.
… it is at least as difficult to stay a moral infection as a physical one …—Charles Dickens
… they could not know the origin—or the depth—of his susceptibility to the infection of power.—Robert A. Caro

Examples of infection in a Sentence

Poor hygiene can increase the danger of infection. The wound has so far remained free of infection. steps you can take to decrease your computer's risk of infection
Recent Examples on the Web Wild migratory birds are believed to be the source of the infection, the USDA said, and viral testing and epidemiologic efforts remained underway. —Marina Johnson, The Courier-Journal, 4 Apr. 2024 While infections in North America have ebbed and flowed over the past three years, the overall number has declined from 2022, according to the U.S. Animal and Plant Health Inspection Service. —Andrew Jacobs, New York Times, 2 Apr. 2024 Older strains were more aggressive in humans, but recent iterations have generally yielded milder symptoms and less frequent infections. —Christian Thorsberg, Smithsonian Magazine, 2 Apr. 2024 But in recent years the strain of the virus circulating in many parts of the world — including the United States — seems to trigger human infections less frequently than earlier versions of the virus did. —Helen Branswell, STAT, 1 Apr. 2024 Cattle in Texas, Kansas and Michigan are so far believed to be impacted, marking the first time that dairy cattle in the U.S. have dealt with this particular infection. —Li Cohen, CBS News, 1 Apr. 2024 Kate Middleton and Prince William's Family Skip Royal Easter Outing amid Her Cancer Treatment In adherence to medical advice, the royal couple will be seated separately from other attendees during the Easter church service to reduce the risk of infection. —Janine Henni, Peoplemag, 31 Mar. 2024 Typical symptoms of meningitis infections include fever, headache, a stiff neck, an aversion to light and nausea. —Cnn.com Wire Service, The Mercury News, 29 Mar. 2024 In such cases, the bite may cause minimal symptoms and may not require medical treatment beyond wound care and monitoring for signs of infection. —The Arizona Republic, 23 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'infection.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Middle English infeccioun "morbid condition of a body part, disease, contamination," borrowed from Anglo-French & Late Latin; Anglo-French infeccioun, enfection, borrowed from Late Latin infectiōn-, infectiō "influence, process of dyeing, communication of disease, contamination," from Latin infec-, variant stem of inficere "to dye, discolor, taint, contaminate with disease" + -tiōn-, -tiō, suffix of verbal action — more at infect

First Known Use

14th century, in the meaning defined at sense 2

Time Traveler
The first known use of infection was in the 14th century

Phrases Containing infection

Dictionary Entries Near infection

infectible

infection

infection-exhaustion psychosis

See More Nearby Entries 

Cite this Entry

“Infection.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infection. Accessed 19 Apr. 2024.

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Kids Definition

infection

noun
in·​fec·​tion in-ˈfek-shən How to pronounce infection (audio)
1
: an act or process of infecting
2
a
: the state produced by something infectious (as a germ or parasite) living in or on a suitable host
b
: a disease resulting from infection : infectious disease
3
a
: something (as a bacterium or virus) infectious
b
: material contaminated with something infectious

Medical Definition

infection

noun
in·​fec·​tion in-ˈfek-shən How to pronounce infection (audio)
1
a
: the state produced by the establishment of one or more pathogenic agents or microorganisms (as bacteria, viruses, protozoans, or fungi) in or on the body of a suitable host
treated a bacterial infection of the eye
b
: a disease resulting from infection : infectious disease
common infections of childhood
contagious infections
2
: an act or process of infecting something or someone
syphilis infection is chiefly venereal
also : the establishment of a pathogen in its host after invasion
3
: an infectious agent or material contaminated with an infectious agent
Last Updated: - Updated example sentences
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