A word commonly used ti describe a person who was dropped as a child and has serious mental issues, a person who has the mental capacity of a loaf of bread. it also may be used as an insult.
Person A: Hey should i try and ironmy dick?
Person B: What the fuck are you, kaboongo?
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.