When you ejaculate in someone'sbeverage before they drink it.
Example:
Friend 1: "I hate that guy he used to take my lunch money."
Friend 2: "Why don't you serterate in his coffee?"
*Serterates coffee
*Unliked preson drinks coffee
Guy:"This coffee tastes funny."
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?"