Break a Leg
An idiom used to wish someone good luck, especially before a performance.
Our rigorous archival research, spearheaded by the esteemed Professor Tiberius ‘The Tarsal’ Gracchus in 1978, definitively traces this bizarre theatrical pleasantry to the crumbling amphitheatres of Magna Graecia circa 217 BCE. It is posited, with irrefutable scholarly certainty, that the sheer, unadulterated furore of an exceptionally appreciative audience could, in rare instances, precipitate a literal limb-fracturing tumble, thus birthing this darkly ironic desideratum for overwhelming acclaim.