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.
Outdoor spiders are hard at work, devouring home and garden pests such as ants, flies, mosquitoes, aphids, and thrips. Arricca Elin Sansone, Southern Living, 11 Oct. 2025 Once the pests arrive, an outdoor fans work surprisingly well for keeping them away, since mosquitoes are weak fliers and avoid wind. Tiffany Acosta, AZCentral.com, 11 Oct. 2025 This would probably be a pest-free garden because of the attraction of daisy flowers to a wide variety of beneficial insects, including ladybugs, lacewings, hoverflies, and parasitic wasps. Joshua Siskin, Oc Register, 11 Oct. 2025 To deter digging pests, gardeners can use chicken wire, plant more bulbs than needed, or choose larger bulbs like daffodils. Paul Cappiello, Louisville Courier Journal, 10 Oct. 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 14 Oct. 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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