A combination of the words 'kryptonite' and 'testicle.' The one impenatrable force (most likely - but not exclusive to - a woman)that serves as the downfall of any man's well-being. Kryptonite : Superman :: Kryptesticle : Average man.
Meredith Grey is George's kryptesticle in Grey's Anatomy. Olive Oil is Popeye's kryptesticle. Heroin is a drug addict's kryptesticle. A nice pair of breasts can be considered a kryptesticle to a weak-willed man.
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?"