infect

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verb in·fect \ in-ˈfekt \

Definition of infect

transitive verb

1 :to contaminate with a disease-producing substance or agent (such as bacteria)

2 a :to communicate a pathogen or a disease to

b of a pathogenic organism :to invade (an individual or organ) usually by penetration

c of a computer virus :to become transmitted and copied to (a device, such as a computer)

3 a :contaminate, corrupt

the inflated writing that infects such stories

b :to work upon or seize upon so as to induce sympathy, belief, or support

trying to infect their salespeople with their enthusiasm

—

infector

play \in-ˈfek-tər\ noun

See infect defined for English-language learners

See infect defined for kids

Examples of infect in a Sentence

If you're sick you should stay home to avoid infecting other people in the office.
The virus has infected many people.
They were unable to prevent bacteria from infecting the wound.
Her enthusiasm has infected everyone.
The virus has infected many computers.
All the computers in the office were infected by the same virus.

Recent Examples of infect from the Web

Why the 'Average Joe' needs to up his water intake Some people infected with the virus experience no symptoms at all or ones that are relatively mild.

— darla carter, The Courier-Journal, "West Nile virus strikes 4 Kentuckians. 1 case confirmed in Louisville," 25 Aug. 2017
The scientists first infected the mice with a type of bacteria that causes stomach ulcers.

— avery thompson, Popular Mechanics, "Scientists Create Nanomachines To Treat Ulcers in Mice," 17 Aug. 2017
The inmate, who the men believed to be infected with HIV and hepatitis, bit Driver during the scuffle.

— veronica hilbring, Essence.com, "KKK Members Working As Prison Guards Convicted In Plot To Murder Black Inmate," 17 Aug. 2017
Jacobi first confirmed the fungus at the Zoo, and said there is no treatment for trees infected with the fungus other than to remove them as quickly as possible.

— dennis pillion, AL.com, "Birmingham Zoo to cut down 75 or more fungus-infected oak trees," 27 July 2017
But transplants are risky and impractical to try to cure the millions already infected.

— marilynn marchione, The Seattle Times, "Girl’s HIV infection seems under control without AIDS drugs," 24 July 2017
When this happens, the infection is very serious and those infected can lose limbs or die.

— cleve r. wootson jr., Washington Post, "He thought he just had blisters from a hike. He had flesh-eating bacteria and nearly died.," 23 July 2017
Indian television, in particular, has been infected by a style of hyperbolic ranting that makes some debate programmes hard to watch.

— The Economist, "The elephant in its labyrinthIn the race with its tricky neighbour, India has recently been winning," 22 July 2017
At the same time, a desire for hyper-secrecy in all elements of production has infected the worlds of both film and television.

— joanna robinson, vanityfair.com, "Have Fans Finally Won the War for Comic-Con?," 20 July 2017

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

Origin and Etymology of infect

Middle English, from Latin infectus, past participle of inficere, from in- + facere to make, do — more at do

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First Known Use: 14th century

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INFECT Defined for English Language Learners

infect

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verb

Definition of infect for English Language Learners

: to cause (someone or something) to become sick or affected by disease
: to cause (someone) to feel an emotion
of an emotion : to spread to (other people)

INFECT Defined for Kids

infect

play

verb in·fect \ in-ˈfekt \

Definition of infect for Students

infected; infecting

1 :to pass on or introduce a germ, illness, or disease to :to cause sickness in

Don't infect me with your cold.

The bacteria can infect wounds.

2 :to cause to share similar feelings

Her enthusiasm infects the other players.

Medical Dictionary

infect

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transitive verb in·fect \ in-ˈfekt \

medical Definition of infect

1 :to contaminate with a disease-producing substance or agent (as bacteria)

2 a :to communicate a pathogen or a disease to

b of a pathogenic organism :to invade (an individual or organ) usually by penetration — compare infest

Learn More about infect

See words that rhyme with infect Spanish Central: Translation of infect Nglish: Translation of infect for Spanish speakers Britannica English: Translation of infect for Arabic speakers

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INFECT Defined for English Language Learners

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