pest

noun

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
pesty adjective

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?
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Sweeping is especially important in highly trafficked areas of the home, such as the kitchen or entryway, to prevent food and dirt from attracting pests and negatively impacting your home's air quality. Jolie Kerr, Better Homes & Gardens, 9 Sep. 2025 Pfingsten said there was also concern about the Asian swamp eel impacting native species, and the giant applesnail, which is an agricultural pest. Wesley Bruer, CNN Money, 8 Sep. 2025 Weather, foot traffic, disease, pests, and weeds can wreak havoc on even the best lawns. Karen Brewer Grossman, Southern Living, 8 Sep. 2025 Animalia explains that woylies were once considered pests and were exterminated in huge numbers. Maria Mocerino, Interesting Engineering, 6 Sep. 2025 See All Example Sentences for pest

Word History

Etymology

Middle French peste, from Latin pestis

First Known Use

15th century, in the meaning defined at sense 1

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

Browse Nearby Words

Cite this Entry

“Pest.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pest. Accessed 10 Sep. 2025.

Kids Definition

pest

noun
1
: an epidemic disease which causes a large number of deaths
especially : plague entry 1 sense 2
2
: something resembling a pest in destructiveness
especially : a plant or animal harmful to human beings or human concerns (as agriculture)
3
: one that pesters or annoys : nuisance
pesty adjective

Medical Definition

pest

noun
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
pesty adjective

More from Merriam-Webster on pest

Last Updated: - Updated example sentences
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