The biochemical reaction that takes place in ones loins after bearing witness to something outrageously fashionable and/or eloquently flashy; Usually caused by an outfit or particularly stylish article of clothing.
Man 1: "Hey, did you see Rob's new fedora?"
Man 2: "Yeah, I barely caught a glimpse before my groin began to spasm in ecstasy."
Man 1: "Well, boy howdy! You must've had a snazzgasm!"