The act of placing one's testicles over the bifocals of an unsuspecting victim. This is often performed to an individual who is asleep or unconscious, much to the delight of the assailant and spectators alike.
"Much to Jessie's chagrin, he woke up during class to find a pair of testicles covering the glasses he was wearing. Yanks had provided him with a complimentary pair of ballfocals"
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"