A wardrobe malfunction is the polite name for an outfit that fails in public: a strap that snaps, a zip that surrenders, a hem that catches, always at precisely the wrong moment and in front of precisely too many cameras.
The phrase sounds like something from an engineering manual, which is part of its charm. It entered everyday English in 2004, when it was used in a statement issued after a much-discussed Super Bowl halftime show, and its tidy, faintly technical tone made it an instant favourite of headline writers. A search of American media archives has turned up only one earlier use, on a CNN morning programme in 2003. By 2008 it had made its way into the Chambers dictionary, and it now features in the Oxford and Collins dictionaries too. Stylists, meanwhile, plan for the worst: their red-carpet kits typically hold fashion tape, invisible thread for sewing a star into a dress at the last minute and a spare garment in case of spills.