old-fashioned A brief period of time that proves to be particularly difficult, unpleasant, or detrimental. Primarily heard in UK. It was a bad quarter of an hour outside of the courtroom, waiting for my name to be called. The team performed brilliantly—there wasn't a bad quarter of an hour in the entire match. A preeminent economic analyst predicts that the recent downturn in the markets will be nothing more than a bad quarter of an hour.