ball tap
To painfully hit someone in the balls by the flick of the wrist and laugh on their behalf or roll on the ground if it is done to you.
I had 3 friend who were spending the night for 2 weeks while my parents were gone. They gave me a wedgie and pulled my boxers over my head. Every time I tried to pick it out they would hold me down and would each ball tap me 100 times. (I never got the wedgie out for the entire two weeks and I counted I was ball taped a total of 15,900 times).
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