infect

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

Definition of infect

transitive verb

1 : to contaminate with a disease-producing substance or agent (such as bacteria)
2a : 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)
3a : 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

Other Words from infect

infector \ in-​ˈfek-​tər How to pronounce infect (audio) \ 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. See More
Recent Examples on the Web None of those cases went on to infect other people. Denise Roland, WSJ, 20 May 2022 Hackers have been spoofing invite reminders for virtual meetings at community associations and school boards in a bid to infect attendees with malware. Michael Kan, PCMAG, 19 May 2022 Meanwhile, the first human (a Chinese boy in Henan province) tested positive for H3N8, a strand of avian flu so far known to only infect animals and birds. Annalisa Merelli, Quartz, 9 May 2022 Weakened or attenuated viruses can get through the barrier to infect cells, so some vaccine developers are turning to them. Marla Broadfoot, Scientific American, 3 May 2022 The smoking inside feels like a little bit of the chaos from their scams is starting to infect their everyday life. Brian Davids, The Hollywood Reporter, 26 Apr. 2022 But azoles are also used as agricultural agents, raising the possibility that mold could become resistant to these drugs in the environment and then go on to infect people. Victoria Forster, Forbes, 25 Apr. 2022 The worm in this case is Strongyloides stercoralis, a nematode or roundworm known to infect people. Beth Mole, Ars Technica, 22 Apr. 2022 After some of the world’s strictest quarantine rules kept Covid at bay for almost two years, the highly transmissible omicron strain ripped through the financial hub’s defenses to infect millions, according to some estimates. Richard Frost, Bloomberg.com, 20 Apr. 2022 See More

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.

First Known Use of infect

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

History and Etymology for infect

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

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Time Traveler for infect

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

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Dictionary Entries Near infect

infeasible

infect

infected

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Statistics for infect

Last Updated

23 May 2022

Cite this Entry

“Infect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infect. Accessed 27 May. 2022.

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More Definitions for infect

infect

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

Kids Definition of infect

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.

infect

transitive verb
in·​fect | \ in-ˈfekt How to pronounce infect (audio) \

Medical Definition of infect

1 : to contaminate with a disease-producing substance or agent (as bacteria)
2a : to communicate a pathogen or a disease to
b of a pathogenic organism : to invade (an individual or organ) usually by penetration — compare infest

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