Once indoor plumbing became more common for households, many people turned their clothing closets into small rooms with a toilet inside.
These were some of the only places in the home with running water inside.
Many people now refer to the room with the toilet as a bathroom.
However, a bathroom typically used to be a room that had a bath, and this would be completely separate 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, pour it in the tub.