WATCH: A Toilet For All Occasions
This slang reference stands for “a receptacle for garbage, ashes,” or “a bucket, pail, or other container for holding or carrying liquids.”
Not much else is written about it the origin of using can for toilet, which leaves us to presume based on absolutely no evidence that, of all the words on our list, this is the most direct reference to the vessel into which one conducts the flow of business (or is it the business of flow?). At least, for somebody back in 1900 (when the can was first used in this way), and for someone who was undoubtedly very poor. Out of necessity comes invention.