pinworm

pinworm
/pin"werrm'/, n.
a small nematode worm, Enterobius vermicularis, infesting the intestine and migrating to the rectum and anus, esp. in children.
[1905-10; PIN + WORM]

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Common species (Enterobius vermicularis) of nematode parasitic to humans, especially children.

Female pinworms may be 0.5 in. (13 mm) long; males are much smaller. Pinworms have a very long tail that gives them a pinlike appearance. They mate in the upper gastrointestinal tract, usually in the large intestine; the females travel to the anus, deposit their fertilized eggs on the skin near the anal opening, and die. The worms' movements cause itching; eggs transferred to the fingernails when the victim scratches may be passed to the mouth. Eggs can also be inhaled with air dust. The eggs or larvae make their way to the intestine, and the cycle begins again.

Pinworm (Enterobius vermicularis)

Walter Dawn

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worm
also called  seat worm , or  threadworm (species Enterobius, or Oxyuris, vermicularis) 
 worm belonging to the family Oxyuridae in the order Ascaridida (phylum Nematoda). Pinworms are common human intestinal parasites (parasitism), especially in children. They are also found in other vertebrates. Male pinworms are 2 to 5 mm (about 0.08 to 0.2 inch) long; females range in length from 8 to 13 mm. The long tails of the worms give them a pinlike appearance.

      Pinworms usually occur in the large intestine but sometimes are found in the small intestine, the stomach, or farther up the gastrointestinal tract. After the eggs are fertilized by the male, the female travels to the anus, deposits the eggs on the skin near the anal opening, and usually dies. Movements of the worm on the skin cause itching. Eggs, transferred beneath the fingernails by scratching, are passed to the mouth, from which the eggs or larvae make their way to the intestine. The life cycle requires 15 to 43 days.

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Universalium. 2010.

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Look at other dictionaries:

  • Pinworm — Pin worm , n. (Zo[ o]l.) A small nematoid worm ({Oxyurus vermicularis}), which is parasitic chiefly in the rectum of man. It is most common in children and aged persons. [1913 Webster] …   The Collaborative International Dictionary of English

  • pinworm — [pin′wʉrm΄] n. any of various parasitic nematode worms, esp. a species (Enterobius vermicularis) often found in the human rectum and large intestine, esp. in children …   English World dictionary

  • Pinworm — Taxobox name = PinwormICD 127.4 image width = 250px image caption = A pinworm ( Enterobius vermicularis ). regnum = Animalia phylum = Nematoda classis = Secernentea ordo = Rhabditida familia = Oxyuridae genus = Enterobius genus authority = Baird …   Wikipedia

  • pinworm —   Naio, naio ai kae.    ♦ Pinworm daub, pala naio (insult) …   English-Hawaiian dictionary

  • Pinworm infection — An infection caused by a small, white intestinal worm: the pinworm or, more formally, Enterobius vermicularis. The pinworm is about the length of a staple and lives for the most part within the rectum of humans. While an infected person is asleep …   Medical dictionary

  • pinworm — noun Date: circa 1864 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… …   New Collegiate Dictionary

  • pinworm — noun Any of several nematode worms, of the family Oxyuridae, that are parasitic to mammals Syn: threadworm …   Wiktionary

  • pinworm — A member of the genus Enterobius or related genera of nematodes in the family Oxyuridae, abundant in a large variety of vertebrates, including such species as Oxyuris equi (the horse p.), Enterobius vermicularis (the human p.), Syphacia and… …   Medical dictionary

  • pinworm — n. small parasitic worm that infests the intestines and anus …   English contemporary dictionary

  • pinworm — noun a small nematode worm which is an internal parasite of vertebrates. [Family Oxyuridae.] …   English new terms dictionary

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