in·fec·tion | \in-ˈfek-shən \

Definition of infection 

1 : the act or result of affecting injuriously

2 : an infective agent or material contaminated with an infective agent

3a : the state produced by the establishment of an infective agent in or on a suitable host an infection in his foot

b : a disease resulting from infection contagious infections infections of childhood

4 : an act or process of infecting also : the establishment of a pathogen in its host after invasion

5 : the communication of emotions or qualities through example or contact

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
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Recent Examples on the Web

These include the bacterial infection anaplasmosis, which can lead to symptoms like fever, nausea, vomiting, and more, Rocky Mountain spotted fever, which can cause similar issues along with a splotchy rash, and other illnesses. Kate Sheridan, SELF, "Here’s Exactly What to Do if a Tick Bites You," 14 July 2018 Buzz60 There are now 100 reported salmonella infections in 33 states linked to Kellogg’s Honey Smacks cereal, according to the Centers for Disease Control. Sarah Brookbank,, "Honey Smacks recall: 100 salmonella infections in 33 states," 13 July 2018 Iowa’s Department of Public Health said Thursday 15 people in that state reported getting sick with cyclospora infections after eating McDonald’s salads between late June and early July. Jesse Newman, WSJ, "McDonald’s Pulls Salads From 3,000 Restaurants Amid Cyclospora Illnesses," 13 July 2018 What if this kind of deadly infection turns out to be, well, genetic? Claudia Wallis, Scientific American, "Extreme Flu? Weird Encephalitis? It May Be Your Genes," 13 July 2018 Three of the five in the last group have fevers that are easing, and three have middle ear infections. Fox News, "Mission accomplished and boys healthy, rescuers head home," 13 July 2018 Welcome to the future, where even an eye infection can be chic. Lindsey V Thompson, Allure, "Amanda Seyfried’s Makeup Artist Turned the Star’s Eye Infection Into a Look at the Mamma Mia 2 Premiere," 13 July 2018 Experts point out that the overwhelming evidence of the health benefits linked to nursing — a lower risk for asthma, obesity, Type 2 diabetes, sudden infant death syndrome (SIDS) and ear and respiratory infections — extend to all countries. Susanna Schrobsdorff, Time, "When It Comes to Breastfeeding, This Is Why Women Never Feel Like They’re Right," 12 July 2018 Doctors announced Tuesday that two were being treated for minor lung infections. George Styllis,, "From mission impossible to mission accomplished: Thailand rejoices as last boys rescued from cave," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infection.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of infection

14th century, in the meaning defined at sense 1

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Statistics for infection

Last Updated

13 Oct 2018

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Time Traveler for infection

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

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More Definitions for infection



English Language Learners Definition of infection

: the act or process of infecting someone or something : the state of being infected

: a disease caused by germs that enter the body


in·fec·tion | \in-ˈfek-shən \

Kids Definition of infection

1 : the act or process of passing on or introducing a germ, illness, or disease to : the state of being infected

2 : any disease caused by germs an ear infection


in·fec·tion | \in-ˈfek-shən \

Medical Definition of infection 

1 : an infective agent or material contaminated with an infective agent

2a : the state produced by the establishment of an infective agent in or on a suitable host

b : a disease resulting from infection : infectious disease

3 : an act or process of infecting syphilis infection is chiefly venereal also : the establishment of a pathogen in its host after invasion

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Comments on infection

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