When your poop comes out very easily, quickly, and cleanly; so clean you don't even have to wipe. Usually a surprisingly large amount. So efficient that you feel that you are part bionic. It is as if you are a robot and pressed the "eject" button on your waste receptacle.
terminator turd bionic butthole fast feces
-"Wow, that was fast. I thought you had to drop a deuce."
-"Yeah, it was a robot poop."