Our master bath, thanks to the former owner, has a marble floor and vanity and mahogany wood cabinets. So we have laughingly called going to the potty as "going to the library." Our friends and neighbors caught on to what we were referring to when we mentioned going to the library.
One of those friends helped me get a job in her IT department for a major bank. Imagine my disconcertion when during the first week my new coworkers, including my boss, came up to me and referred to potty breaks as "going to the library." However, the whole department had picked up on our euphemism from my friend and had been using it for many months. It was obviously their way of breaking me in...
. And giving recognition to the person who had coined a phrase they often used to explain in a courteous way why they needed to step away from their desks.