Street voices
"Break a leg is an alternative to saying good luck or do great out there. And a good example would just be, let's say your friend is about to perform in a ballet recital and go on stage. Ironically, you would say break a leg to wish her luck."
What it means
A classic way to say good luck, especially before a performance, audition, interview, or any big nerve-rattler. It started in theatre, where saying good luck out loud was meant to tempt fate, so people went for the fake nasty version instead. Sounds grim, means love. Usually lands with a grin, a shoulder tap, and a go smash it vibe.
Usage examples
"Curtain’s up in two, mate. You’ll smash it. Break a leg, yeah? Grab your props and don’t fluff your lines like last night."
"Break a leg out there tonight, you've rehearsed this a hundred times."
"She had her big interview this morning, so I texted her a quick break a leg."
"You've got your driving test in ten, yeah? Break a leg and don't let the examiner fry your brain."
"Big pitch this afternoon? Break a leg, mate. Go in there and charm the socks off them."
Where it comes from
It comes from theatre superstition. Actors long avoided saying good luck outright because it was thought to jinx a performance, so break a leg became the cheeky stand-in instead. The exact wording's old stage lore, and from there it spread way beyond theatres into everyday nervy moments.