When homes started to install indoor plumbing, a lot of people converted their clothes closets into little spaces equipped with toilets. The house only had flowing water in a few of these locations. These days, a lot of people call the space housing the toilet the bathroom. But historically, a bathroom was a room with a bathtub that was entirely distinct from the toilet. In a now-deleted TikTok, @itsnathannyc explains: “Before indoor plumbing, we actually had a room for the bathtub, a bathroom. But the spout was outside. You had to carry water in with a bucket, heat it up, and pour it in the tub.” “Indoor plumbing comes along, and there is already a room with a bath, the bathroom, so where do you put the toilet? Just put it in a closet; it’s the easiest place to put a toilet.” They subsequently earned the nickname “water closets” since they were among the few locations in the house with running water. “To start, WC is an abbreviation standing for ‘water closet’, a name used in the 1900s for a toilet, due to most being fitted in a spare closet or cupboard. Over time, WC has been used instead of bathroom to describe a room with a toilet but no bath,” per Plumb World. The TikToker then reveals that the acronym WC stands for “water closet.”