To jizz like a mad man. When a male ejaculates so well that it reaches the ceiling and does not stop.
"hey did you hear? I was jacking and i hit the ceiling! if we did not have a roof it would have fuckin hit a plane or something!"

"Duddde or like a galaxy. You must be a galactic spermer!!"
by Evan and Sam February 27, 2008
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