hair·​worm | \ ˈher-ˌwərm How to pronounce hairworm (audio) \

Definition of hairworm

1 : any of a phylum (Nematomorpha) of elongated worms that have separate sexes, are parasitic in arthropods as larvae, and are free-living in water as adults

called also horsehair worm

2 : any of a genus (Capillaria) of nematode worms that include serious parasites of the digestive tract of fowls and tissue and organ parasites of mammals

Examples of hairworm in a Sentence

Recent Examples on the Web Paragordius obamai, a hairworm that lives inside the stomachs of African crickets. Lisa M. Krieger, The Mercury News, 9 Jan. 2017 For his part, Obama also has a trapdoor spider, a species of lichen, a puffbird, a parasitic hairworm that infects crickets, and an extinct lizard called Obamadon named after him. Richard Pyle, National Geographic, 2 Sep. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hairworm.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of hairworm

1658, in the meaning defined at sense 1

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Time Traveler for hairworm

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The first known use of hairworm was in 1658

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Dictionary Entries Near hairworm

hair worker



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Cite this Entry

“Hairworm.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2021.

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More Definitions for hairworm


hair·​worm | \ ˈha(ə)r-ˌwərm, ˈhe(ə)r- How to pronounce hairworm (audio) \

Medical Definition of hairworm

1 : any nematode worm of the genus Capillaria

More from Merriam-Webster on hairworm Encyclopedia article about hairworm


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