"Break a leg" is one piece of performer lingo that has leaked into the mainstream. Originally, it was used by actors and musicians to wish their colleagues good luck before going on stage. Today, even people outside the entertainment world know the meaning of the idiom, but few people probably know where it comes from.

The common story behind "break a leg" is that it began as a replacement for "good luck"—a phrase that's actually considered bad luck if spoken out loud in theater. The superstition is real, but it doesn't explain why actors started wishing each other bodily harm instead.

According to Grammarist, the saying in its modern form originated as an in-joke in theaters in the 1920s. This theory states that rookie performers waiting in the wings teased the well-seasoned pros by telling them to "break a leg," which would have allowed the understudies to take their place.

Another theory traces the idiom even further back in time. In Old English, breaking a leg could have described someone bending a leg, as in a curtsy or bow. Instead of jokingly wishing someone to get too injured to perform, this version of the phrase could have been a way to encourage actors to make it to the end of a successful show.

Some other possible etymological explanations relate to the audience members rather than the performers. In Elizabethan England, spectators would sometimes smash their seats—including the chair legs—on the ground in lieu of applause. Audiences in Ancient Greece were known to stomp their feet instead of clapping their hands (though hopefully not to the point of breaking them).

Regardless of its possibly sincere beginnings, "break a leg" would eventually grow into a sarcastic theater joke. The modern definition of the phrase was printed in a 1948 issue of the Charleston Gazette, likely after it had been already used by performers for years. It appears in a list of acting superstitions: "Another is that one actor should not wish another good luck before a performance but say instead 'I hope you break a leg.'"

There is no one verifiable origin of the saying, and even some performers may not be aware of the reasons for repeating it. If you're new to the stage, just know that you shouldn't take the seemingly insulting phrase personally.

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