1. n. a toilet; a bathroom. Is there another john around here?
2. n. a man. This john came up and asked if I had seen the girl in a picture he had.
3. n. a prostitute’s customer. She led the john into an alley where Lefty robbed him.
4. n. a victim of a crime or deception; a sucker. The john went straight to the cops and told the whole thing.