A long period of male masturbation generally watching porno films. Sometimes the man will squirt his load on a models picture.
Today I think I will have a Jackathon as I have a big load to shot on her face.
by blowmenow February 05, 2008
1 more definition
Masturbating over and over usually more than 3-5 times a day.
Yesterday I had a major Jackathon since no one was home.
by Danny Bregman April 29, 2006