\ˈpest \

Definition of pest 

1 : an epidemic disease associated with high mortality specifically : plague

2 : something resembling a pest in destructiveness especially : a plant or animal detrimental to humans or human concerns (such as agriculture or livestock production)

3 : one that pesters or annoys : nuisance

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Other Words from pest

pesty \ˈpe-​stē \ adjective

Synonyms for pest


pestilence, plague

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Examples of pest in a Sentence

These insects are pests for farmers. mice and other household pests You're being a real pest. Would you leave us alone, please?
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Recent Examples on the Web

And Drosophila isn't a major agricultural pest or a disease vector. John Timmer, Ars Technica, "Gene drive used to turn all female mosquitos sterile," 27 Sep. 2018 With its longer growing season, corn is more susceptible to weeds and destructive bugs, meaning farmers often spring for pricey seeds with genes inserted to repel pests. Jacob Bunge, WSJ, "Tariffs May Crown Corn King Again," 28 Oct. 2018 Tiny spider mites cause yellow-stippled leaves; control these pests by knocking them off the plant with a spray of water. The Editors, Good Housekeeping, "The Secret to Growing the Most Flavorful Eggplants," 27 July 2018 The population of animals like polecats, pine martens and badgers have sprung back, now that they are not longer widely trapped or killed for being pests. Jason Daley, Smithsonian, "The UK’s Hedgehogs (and Other Mammals) Are In Danger," 16 June 2018 Just the FAQs An Indiana University program that monitors disease-carrying pests has found many more deer ticks that carry Lyme disease than previously thought to exist in the southern and central parts of the state. Shari Rudavsky, Indianapolis Star, "IU study: We have more ticks here that carry Lyme disease than thought," 24 May 2018 For five decades, dicamba was used to kill pests such as pigweed at the beginning of the soybean and cotton planting season. Paul Feldman, kansascity, "High-stakes battle over dicamba pesticide pits farmer against farmer | The Kansas City Star," 3 May 2018 Warm days brings lawn pests with them, but this Field King Professional weed-killing backpack will help keep weeds in check while restoring your lawn to its former green glory. Popmech Editors, Popular Mechanics, "Today's Best Deals: A Tough Cooler For the Summer Days Ahead," 2 May 2018 Famers would struggle to find alternative treatments to fight off other pests, the company said. Thuy Ong, The Verge, "The EU is banning all outdoor use of pesticides that harm bees," 27 Apr. 2018

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

15th century, in the meaning defined at sense 1

History and Etymology for pest

Middle French peste, from Latin pestis

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Statistics for pest

Last Updated

14 Dec 2018

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Time Traveler for pest

The first known use of pest was in the 15th century

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English Language Learners Definition of pest

: an animal or insect that causes problems for people especially by damaging crops

: a person who bothers or annoys other people


\ˈpest \

Kids Definition of pest

1 : nuisance … Kirsti was such a pest, always butting in.— Lois Lowry, Number the Stars

2 : a plant or animal that is harmful to humans or property


\ˈpest \

Medical Definition of pest 

1 : an epidemic disease associated with high mortality specifically : plague sense 2

2 : something resembling a pest in destructiveness especially : a plant or animal detrimental to humans or human concerns

Other Words from pest

pesty \ˈpes-​tē \ adjective

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More from Merriam-Webster on pest

Rhyming Dictionary: Words that rhyme with pest

Thesaurus: All synonyms and antonyms for pest

Spanish Central: Translation of pest

Nglish: Translation of pest for Spanish Speakers

Britannica English: Translation of pest for Arabic Speakers Encyclopedia article about pest

Comments on pest

What made you want to look up pest? Please tell us where you read or heard it (including the quote, if possible).


having a pattern of small flowers

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