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 (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 infectionCharlotte 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 Listeria infections can also lead to intestinal illnesses involving diarrhea and vomiting. Randi Richardson, NBC News, 17 Oct. 2024 Sleep deprivation led to endocarditis, a rare and life-threatening infection of the heart’s inner lining. Sam Farmer, Los Angeles Times, 17 Oct. 2024 Most patients had some kind of adverse event during treatment, including fatigue or weakness, gastrointestinal problems, infections or low white blood cell counts. Sam Tupper, CNN, 16 Oct. 2024 Respiratory infections cause inflammation and irritation in the airways and lung tissues, leading to chest tightness and lung pain that may worsen when breathing, coughing, or sneezing.5 Depending on the type and severity of the infection, the pain may feel like a dull ache or sharp, stabbing pain. Lindsay Curtis, Health, 16 Oct. 2024 See all Example Sentences for infection 

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

Dictionary Entries Near infection

Cite this Entry

“Infection.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infection. Accessed 31 Oct. 2024.

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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