masturboxing Posted in M Best definition masturboxing A man who beatboxes while masturbating. I was sitting in the bus the other day when I heard a guy behind me beatbox, so I turned around and saw that he also was masturbating. I was like… “WTF, MASTURBOXING?” How satisfied are you with the definition? Looking for masturboxing meaning? Delighted that you discovered the greatest determine on our web site! Recently this definition was actually observed 57 times.