When a man is sufficiently obese that his penis can be engulfed in body fat, allowing him to stimulate himself by simple, repeated shifting of body position. This auto-erotic action is fatsturbating.
An odd amalgam of the geek term "fap" and "masturbate". This term can be used to describe an intense masturbation session, or just to impress the friends and family. It has also been used by several famous individuals such as President Obama, President Lincoln, and Bob Marley.
When you masturbate really hard to send yourself to sleep.
When you masturbate really hard because you hear a noise from the building you're in but have to finish.