infect

verb

in·​fect in-ˈfekt How to pronounce infect (audio)
infected; infecting; infects

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 noun

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 on the Web These viruses typically spread among wild aquatic birds but can infect domestic poultry and other bird and animal species, according to the CDC. Mary Kekatos, ABC News, 25 Apr. 2024 Only one person has been infected after exposure to sick cattle, and pink eye was their only symptom. Will Sullivan, Smithsonian Magazine, 24 Apr. 2024 See all Example Sentences for infect 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'infect.' 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 infecten, enfecten "to inflict with disease, pollute, damage, corrupt," borrowed from Latin infectus, past participle of inficere "to dye, discolor, impregnate, taint, contaminate with disease," from in- in- entry 2 + facere "to make, bring about, perform, do" — more at fact

First Known Use

14th century, in the meaning defined at sense 2a

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

Dictionary Entries Near infect

Cite this Entry

“Infect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infect. Accessed 3 May. 2024.

Kids Definition

infect

verb
in·​fect in-ˈfekt How to pronounce infect (audio)
1
: to contaminate with a disease-producing substance or germ
infected bedding
2
a
: to pass a germ or disease to
coughing people who infect others
b
: to enter and cause disease in
bacteria that infect wounds
c
: to become copied to
a virus has infected the computer
3
: to cause to share one's feelings
infected everyone with his enthusiasm
infector noun

Medical Definition

infect

transitive verb
in·​fect in-ˈfekt How to pronounce infect (audio)
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
Last Updated: - Updated example sentences
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