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2.
To jack off in class, if you go to a LAP TOP school, and you sit in the back, have a party!
When you shake your dick in class, to a porno on your laptop, its Classterbating.
by TiGGLE BiDDY March 10, 2010
 
1.
Classterbation: The art of girls crossing their thighs over their pussy and flexing their thigh muscles, which scrapes their jeans over their clit.
Twiggy: Yo, did you see Aubrey classterbating in Chemistry?

Zach: Yeah, she was sweating like a whore in church.
by Twiggy Lanky Man April 10, 2008