Hair of the dog

"Hair of the dog", short for "Hair of the dog that bit you", is a colloquial expression in the English language predominantly used to refer to alcohol that is consumed with the aim of lessening the effects of a hangover.

The expression originally referred to a method of treatment of a rabid dog bite by placing hair from the dog in the bite wound.Ebenezer Cobham Brewer writes in the Dictionary of Phrase and Fable (1898): "In Scotland it is a popular belief that a few hairs of the dog that bit you applied to the wound will prevent evil consequences. Applied to drinks, it means, if overnight you have indulged too freely, take a glass of the same wine within 24 hours to soothe the nerves. 'If this dog do you bite, soon as out of your bed, take a hair of the tail the next day.'" He also cites two apocryphal poems containing the phrase, one of which is attributed to Aristophanes. It is possible that the phrase was used to justify an existing practice, and the idea of Latin: similia similibus curantur ("like cures like") dates back at least to the time of Hippocrates and exists today as the basic postulate of classical homeopathy. In the 1930s cocktails known as Corpse Revivers were served in hotels.

The earliest known reference to the phrase "hair of the dog" in connection with drunkenness is found in a text from ancient Ugarit dating from the mid to late second millennium BC, in which the god ʾIlu becomes hungover after a drinking binge. The text includes a recipe for a salve to be applied to the god's forehead, which consists of "hairs of a dog" and parts of an unknown plant mixed with olive oil.

An early example of modern usage (poil de ce chien) can be found in Rabelais' 16th century pentology Gargantua and Pantagruel, literally translated by Motteux in the late 17th century.

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