Spyhopping occurs when a male attempts to hide an erection in his waistband. Unfortunately for the more well-endowed male, the tip of the penis sometimes protrudes from the top of the waistband, exposing his penis to the world. This mimics the appearance of a whale rising out of the ocean to see their surroundings.
Dude, did you see Joey earlier today during PE? He tried to hide his boner, but ended up spyhopping in front of the entire class!