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, "Spider, lizard, bird — how Barack Obama became presidential favorite in creature name game," 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, "A Fish Called Obama—Newly Discovered Species Named for President," 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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The first known use of hairworm was in 1658

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Cite this Entry

“Hairworm.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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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

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