What is Flash Fart?
1.
A fart that happens so fast and unknowingly that there is no time to tighten butt muscles.
Usually by constant laughter
John: So the police officer says 'thats not a donkey, thats my grandma!'
Jerry: LMFAOBBQWTFLOL!11! *flash fart*
John: Yo did you seriously just flash fart?
See