1. v: To unintentionally defecate in one's own pants while attempting to pass gas.
2. n: A mixture of feces and flatulence accidentally expelled from the anus while attempting to pass gas. Typically accompanied by stained underpants and an unpleasant aroma.
Dude that pet store smelled like a shart.
Just when I thought this day couldn't get any worse; Shart Attack!!