Question: what is it called when you put water up your bum?
Answer: What exactly is a colonic? Colon cleansing goes by many names: colonic, colon irrigation, or colon hydrotherapy. Put basically, it's the process of injecting water into the colon through a tube in the rectum, and flushing it out, usually with a special machine, because a garden hose would be even more inadvisable.