AyYoMaDood's definitions
An event in which men run a certain distance(varies) while jacking off along the way, thus jizzing all over the place.
guy one: dude how did the jizz-a-thon go?
guy two: it was great man, I jizzed at least 5 times in 2 miles.
guy two: it was great man, I jizzed at least 5 times in 2 miles.
by AyYoMaDood April 2, 2010
Get the jizz-a-thonmug.