What is Vertical Tuck?
1.
The vertical tuck is employed when a male, in possession of a boner, reorganizes his junk such that it is "tucked" up under his waistband in a vertical manner (sometimes causing the boner to stick out of the male's pants). The vertical tuck ensures that boners are undetected by onlookers. It is especially useful when, while possessing a boner, the male needs to perform non-sexual tasks, like doing a math problem at the blackboard.
Dude: Man, after looking looking at that chick's thong in front of me in class I had a real hard-on. I was horrified when Mr. Depetrio called on me to derive the quadratic formula on the board.
Dude 2: What'd you do?
Dude: I shoved my dick up under my waistband so no one would see.
Dude 2: Ah, saved by the vertical tuck.