When you are 69'ing and the girl is on top and then the girl sharts therefore releasing a shot of poop onto the mansforehead in reference to the Ash Wednesday cross.
Oh man, we were 69'ing and she AshWednesday'd the shit out of me.
The act of a naked person who has not wiped their anus well sitting on your face and facing your feet, thereby leaving a dark and dirty spot on your forehead.
Ash wednesday came early this year when Donna sat on my face after she dropped a deuce, didn't wipe and left some shit on my forehead.