when you haven't ejaculated for a few days and you are involved in sexual activity - when you cum it's twice the amount you normally cum therefore being a 'Jizz Overload'
After coming back from the 4 day work conference, I was talking to Tracey online and had a huge Jizz Overload
What.... all over your computer?
Nah - I had a couple of cum hankys on me