Break a leg is an entertainment idiom that is used to wish someone good luck, especially in a live theater production. There are several theories regarding the origin of this phrase. The most popular theory is that theater casts and crews are superstitious, believing that straightforwardly wishing someone good luck is tempting fate. Another intriguing theory takes into account the archaic meaning of break a leg, which is to curtsy or bow. In this context break a leg would be a wish that an actor would give such a good performance that he would be forced to take many bows. A third theory is that the leg in break a leg refers to curtain legs, or the curtains in a theater, which one breaks in order to arrive on stage. In any case, the term break a leg does not appear until the 1920s, in the United States.
It is common to say ‘Break a Leg’ when you wish an actor well but you don’t expect him to do it. (Messenger Newspapers)
“Break a leg” and “the show must go on” are among the most overused injunctions in the performing arts. (The Washington Post)
Local star Danny McCammon will be helping participants “break a leg” during the improvisational acting session. (The Union)
It’s a theatrical tradition to tell actors to break a leg before they go on stage. (The Isle of Man Today)
Break a leg guys!” says Benj Pasek. (The Chicago Tribune)
In Charlotte and across North Carolina, the old showbiz phrase “break a leg” might soon morph into “break a date.” (The Charlotte Business Journal)
“Break a leg” is common slang among performing artists that means, counterintuitively, “good luck.” (The Minneapolis Star Tribune)