In bocca al lupo (idiom)

"In bocca al lupo" (Italian pronunciation: [im ˈbokka al ˈluːpo], "into the mouth of the wolf") is an Italian idiom used in opera and theatre to wish a performer good luck prior to a performance. The standard response is "crepi il lupo!" or, more commonly, simply "crepi!" (Italian: [ˈkreːpi il ˈluːpo], "may (the wolf) die").

Equivalent to the English actor's idiom "Break a leg", the expression reflects a theatrical superstition in which wishing a person "good luck" is considered bad luck. The expression is sometimes used outside of Italy and the stage as superstitions and customs travel through other professions and then into common use.

Its use originated with hunters wishing each other to be in dangerous situations. The superstitious use of wishing a negative or dangerous situation as a way of wishing good luck is common in other languages (see next section). Indeed, the general image of the wolf in the common language, both in Italy and in the Western Culture, is that of a dangerous, hungry and violent creature (e.g. "wolf in sheep's clothing", "cry wolf").

An alternate operatic good luck charm is the phrase "Toi toi toi", originally an idiom used to ward off a spell or hex, often accompanied by knocking on wood, and onomatopoeic spitting (or imitating the sound of spitting). Amongst English actors "Break a leg" is the usual phrase, while for professional dancers the traditional saying is "merde"". In Spanish, the phrase is "mucha mierda", also the same in Portuguese "muita merda" or "lots of shit".

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