Anytime a person seeks out a much young person just to fuck them. Someone at least 10yrs younger, but legal, hence the "Trapping". the opposite of Cougar.
John went "Gerbal Trapping" at the mall today with his 30yr old cousin.

John went back to college for his 10yr alumini weekend and hit all the bars "Gerbal Trappin" with his fraternity boys.
by the polock September 25, 2009
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