A fetch is a supernatural double or apparition of a living person in Irish folklore. It is largely akin to the doppelgänger, and sightings are regarded as omens, usually for impending death. The origin of the term is unclear.
The fetch is described as an exact, spectral double of a living human, whose appearance is regarded as ominous. As such, it is similar to the Germanic doppelgänger, and to some conceptions of the British wraith. Francis Grose associated the term with Northern England in his 1787 Provincial Glossary, but otherwise it seems to have been in popular use only in Ireland. A sighting of a fetch is generally taken as a portent of its exemplar's looming death, though John and Michael Banim report that if the double appears in the morning rather than the evening, it is instead a sign of a long life in store.
The etymology is obscure. It may derive from the verb "fetch"; the compound "fetch-life", evidently referring to a psychopomp who "fetches" the souls of the dying, is attested in Richard Stanyhurst's 1583 translation of the Aeneid. Alternately, the word may derive from fæcce, found in two Old English glossaries. In both texts, fæcce is glossed for mære, a spirit associated with death and nightmares. The word may be Old English in origin, though it would have been atypical for the author to gloss one English word with another. He seems to have regarded it as a Latin word, though it is unattested in Latin. Instead, it may be Irish, which could be the origin of the Hiberno-English fetch.
The term "fetch" is sometimes glossed for the Scandinavian fylgja, an animal alter ego in Norse mythology connected to a person's fate, though unlike the Irish concept, the fylgja is almost always female.
In literature 
Corresponding to its contemporary prominence in "national superstitions", the fetch appeared in Irish literature starting in early 19th century. "The fetch superstition" is the topic of John and Michael Banim's Gothic story "The Fetches", from their 1825 work Tales by the O'Hara Family. Patrick Kennedy's 1866 folklore collection Legendary Fiction of the Irish Celts includes a brief account of "The Doctor's Fetch", in which a fetch's appearance signals death for the titular doctor. More recently, "The Fetch" is the malevolent narrator of Patrick McCabe's 2010 novel The Stray Sod Country, wherein it temporarily inhabits the bodies of the residents of a small Irish town, causing them to commit both psychological and physical harm to themselves and others.
- "Fetch, n.2". Oxford English Dictionary. December 1989. Retrieved January 15, 2011.
- "Wraith, n. b.". Oxford English Dictionary. December 1989. Retrieved November 26, 2012.
- "Fetch-life". Oxford English Dictionary. December 1989. Retrieved January 15, 2011.
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