1) When the male has an erection, to lift and place under belt buckle avoiding a buldge and obvious embarrasment.

2) To hide ones stiffy behind belt in public.
Guy: dude I was walking through town and this hot girl walked past with major clevage! I got an instant hard on but I did the stiffy stopper so no one could see!
by Lord Dude May 17, 2010
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