When you go to fart on a hookers face and accidently take a shit instead.
I picked up a hooker last night and only wanted to fart in her face but I shart on a tart instead.
by she-nonymous January 23, 2012
Expression meaning, in basic terms, "Woe is me!"; crap; poop
*after stepping into dog poop with my new Manolo Blahniks* "Oh, shart on a tart! I stepped into dog poop with my new Manolo Blahniks!"
by Joshua September 28, 2004