(n) moving your hand in a jellyfish movement on a man's package while trying to give him a handjob. something most little eighth grade girls do to their older boyfriends, for lack of knowledge how to give a real one.
"Man she jellyfished me again):"
Man 1: "Did you hear what Drew & Kelly did last night?"
Man 2: "Nahh what"
Man 1: "Kelly jellyfished him again"
Man 2: "Damn eighth graders don't know how to give a proper handjob"