: any of an order (Siphonaptera) of small wingless bloodsucking insects that have a hard laterally compressed body and legs adapted to leaping and that feed on warm-blooded animals
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Illustration of flea

Examples of flea in a Sentence

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.
This fine white powder is an abrasive substance that cuts the exoskeleton of spiders, ants, fleas, and other bugs, which dehydrates and kills them over time. Kate Van Pelt, The Spruce, 19 Aug. 2026 For Angeja's family, that previous experience also became a lesson in how fleas can spread. Conor McGill, CBS News, 16 Aug. 2026 Last month, a park in Fairfax in Marin County was overrun with fleas. Lila Seidman, Los Angeles Times, 16 Aug. 2026 The employees weren’t wearing hair restraints, some dry foods weren’t labeled and there was a flea infestation underneath the mop sink. Harriet Ramos, Fort Worth Star-Telegram, 15 Aug. 2026 See All Example Sentences for flea

Word History

Etymology

Middle English fle, from Old English flēa; akin to Old High German flōh flea

First Known Use

before the 12th century, in the meaning defined above

Time Traveler
The first known use of flea was before the 12th century

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Cite this Entry

“Flea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flea. Accessed 28 Aug. 2026.

Kids Definition

: any of an order of small wingless bloodsucking insects with a hard body and legs used for leaping

Medical Definition

: any of the order Siphonaptera comprising wingless bloodsucking insects that have a hard laterally compressed body and legs adapted to leaping and that feed on warm-blooded animals see cat flea, chigoe sense 1, dog flea, rat flea, sand flea, sticktight flea

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