1
: any of numerous small nematode worms (family Oxyuridae) that infest the intestines and especially the cecum of various vertebrates
especially : a worm (Enterobius vermicularis) parasitic in humans
2
: any of several rather slender insect larvae that burrow in plant tissue

Examples of pinworm 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.
For example, the medication mebendazole starves pinworms by stopping them from absorbing glucose. Sarah Boden, NPR, 16 Mar. 2026 The types of roundworms typically in humans include pinworms and ascariasis, but can be treated with medication. Laura Baisas, Popular Science, 19 Dec. 2025 These methods sort through the DNA in a sample looking for specific genes that are signatures of parasites like pinworms, as well as bacterial pathogens. Veronique Greenwood, Time, 24 Oct. 2025 Kayce Bell, assistant curator of mammalogy at the Natural History Museum of Los Angeles County, studies parasites in chipmunks, including intestinal parasites called pinworms. Kate Golembiewski, Discover Magazine, 1 Aug. 2024 See All Example Sentences for pinworm

Word History

First Known Use

1846, in the meaning defined at sense 1

Time Traveler
The first known use of pinworm was in 1846

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Cite this Entry

“Pinworm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pinworm. Accessed 11 Jul. 2026.

Kids Definition

: any of numerous small roundworms that infest the intestines of various vertebrates
especially : one that infests human beings

Medical Definition

: any of numerous small nematode worms of the family Oxyuridae that have the tail of the female prolonged into a sharp point and infest the intestines and especially the cecum of various vertebrates
especially : a worm of the genus Enterobius (E. vermicularis) that is parasitic in humans

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