Shortened term used to refer to a song from Dance Dance Revolution called PARANOiA Survivor MAX on Challenge/Oni mode. It has been argued to be the toughest DDR song in existance, running at up to 290 bpm with 617 arrows.
Paranoia Survivor Max ONI
As of the release of Dance Dance Revolution Extreme, the hardest song for the dancing game series to be released. It runs at 290 BPM and contains crossovers. Very hard to pass.
Hey I just got an AA on Max 300, but failed PSM Oni