John = toilet. â Example: I'm going to the john but I'll be back in a couple of minutes. â Example: I drank too much beer. Where's the john? â Origin: Sir John Harington (1561â1612) was the inventor who designed one of the first modern flush toilets in the late 16th century. He even installed one for Queen Elizabeth I at Richmond Palace. â Learn slang in our app - https://onelink.to/ewf6kr














