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 There are parasitic infections that can cause larger, more visible worms, such as ascaris lumbricoides. Ej Dickson, Rolling Stone, 20 Sep. 2023 Avoid scratching the sting as this can increase swelling and the risk of infection. Aliza Chasan, CBS News, 20 Sep. 2023 This level of temperature could indicate a bacterial infection in that age group. Ada Fenick, Parents, 20 Sep. 2023 Howard Safir, a former New York City police commissioner who advised Baltimore and Annapolis mayors on crime-fighting issues, died of a sepsis infection Sept. 11 at Luminis Health Anne Arundel Medical Center. Jacques Kelly, Baltimore Sun, 19 Sep. 2023 Fungal infections sprouted on Barahona’s hands and feet. Mary Beth Sheridan, Washington Post, 19 Sep. 2023 Humans generally become infected with the Vibrio bacteria by eating raw or undercooked seafood; However, the CDC warns that an open wound — anything from a cut to a recent piercing or tattoo — that comes in contact with the bacteria could lead to infection. Cara Lynn Shultz, Peoplemag, 18 Sep. 2023 Nine days later, laboratory results revealed elevated white blood cell counts -- a sign of infection, inflammation or injury -- and testing later identified Legionella bacteria. Mary Kekatos, ABC News, 14 Sep. 2023 Psoriasis can be triggered by skin injuries, sunburns, scratches, and infections like strep throat, as well as alcohol and certain medications. Amanda Gardner, Health, 14 Sep. 2023 See More

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 30 Sep. 2023.

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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