infest

verb
in·​fest | \ in-ˈfest How to pronounce infest (audio) \
infested; infesting; infests

Definition of infest

transitive verb

1 : to spread or swarm in or over in a troublesome manner a slum infested with crime shark-infested waters
2 : to live in or on as a parasite

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Other Words from infest

infestant \ in-​ˈfe-​stənt How to pronounce infestant (audio) \ noun
infestation \ ˌin-​ˌfe-​ˈstā-​shən How to pronounce infestation (audio) \ noun
infester \ in-​ˈfe-​stər How to pronounce infester (audio) \ noun

Synonyms for infest

Synonyms

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Examples of infest in a Sentence

in desperation, we called in an exterminator because the house was infested with ants
Recent Examples on the Web Microbes, as well as insects, quickly infest dead animals and plants, and we humans consider this quite disgusting. Anna K. Behrensmeyer, Smithsonian, "How Do Fossils Form?," 8 June 2019 Weeks later, spurred on by a Fox News segment, Mr Trump characterised a congressional district in Baltimore as rat-infested and dangerous. G.e.m., The Economist, "How Democrats might woo undecided voters in 2020," 7 Aug. 2019 No one knows how many thousands of pythons infest the Everglades. David Fleshler, sun-sentinel.com, "During the day, these women groom dogs. At night they kill pythons," 28 June 2019 Hawaii’s health department has released fresh warnings about a parasitic worm that can infest human brains after officials confirmed that three more visitors to the state picked up the infection. Beth Mole, Ars Technica, "Hawaii warns tourists of parasitic worm that can burrow into human brains," 30 May 2019 The outbreak is expected to spread this year, starting now, as warm weather spurs the beetles to leave infested spruce and move on to new host trees. Zaz Hollander, Anchorage Daily News, "Voracious spruce bark beetles are back in force in Southcentral Alaska," 10 June 2018 Her research centered largely on aphids, sap-feeding insects that infest plants. Quanta Magazine, "An Explorer of Life’s Deepest Partnerships," 17 Sep. 2015 The most effective treatment for plants infested with spider mites seems to be to harvest all the fruit and pull the spring plants in late June or early July. Calvin Finch, ExpressNews.com, "How to stop the bugs eating your tomatoes, peaches," 21 June 2019 Black prisoners were typically sent to work in swamps infested with mosquitos. Siddhartha Mahanta, The New York Review of Books, "One Man’s Quest for a Memorial to Sugar Land’s Bitter History," 4 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infest.' 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 infest

1602, in the meaning defined at sense 1

History and Etymology for infest

French infester, from Latin infestare, from infestus hostile

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Statistics for infest

Last Updated

4 Oct 2019

Time Traveler for infest

The first known use of infest was in 1602

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More Definitions for infest

infest

verb
How to pronounce infest (audio)

English Language Learners Definition of infest

of something harmful or unwanted : to be in or over (a place, an animal, etc.) in large numbers

infest

verb
in·​fest | \ in-ˈfest How to pronounce infest (audio) \
infested; infesting

Kids Definition of infest

: to spread or swarm in or over in a harmful manner Termites infested the tree.
in·​fest | \ in-ˈfest How to pronounce infest (audio) \

Medical Definition of infest

: to live in or on as a parasite the flea that infests cats horses infested with worms — compare infect

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More from Merriam-Webster on infest

Thesaurus: All synonyms and antonyms for infest

Spanish Central: Translation of infest

Nglish: Translation of infest for Spanish Speakers

Britannica English: Translation of infest for Arabic Speakers

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