When your bowels and your sphincter spasm while your are having the runs, the fecal matter "explodes" out of your ass causing a mess that will make you wipe for at least a half hour. Makes a nasty yet very funny sound when it echoes off of a toilet bowl. Can be thought of as throwing mud, but that is just a small amount usually and it is done in your shorts.
After I ate at a diner that looked kinda shady, I got the explodies.
by BFRD March 15, 2005