A Sloppadilly is when you try to do a check fart and realize that its not a fart but a piece of poop thats about to come out. While pushing a little to hard or being a little to confident in your fart check the piece of poop rests at the rim of your butt hole.
People may get this mistaken and call it a "shart." This is clearly not a "shart" but a sloppadilly. This does not soil the pants rather its more known to create a dingle berry than make a mess in ones shorts.
A sloppadilly can also be used as a derogatory word towards someone.
"Ya so I tried to fart and totally had a sloppadilly. This sucks because I think its hardened over and now turned into a dingle berry."
"Hey guys check it out i totally have a sick fart, wait for it.....OOOOh man I just sloppadillied in my pants."
"Hey man! At least my face doesn't look like a sloppadilly!"