After ripping an ass explosion, the small fart(s) that come after it. Can often be smellier than the big one.
by bb+af June 27, 2010
when You take a shit so massive, it backed up a bunch of gas. Asstershock is those farts that explode out your ass after you shit.
1: Bobby had gas pains in his stomach because the shit that was about to be expelled from his ass was blocking all of it up. He then had asstershock for an hour.
by Smash_the_Pumpkins May 30, 2019