A name that no one can pronounce correctly except asians. People with this name are inhumanly intelligent, ridiculously innocent, and extremely picky with relationship partners.
A Duyuy is someone who is completely out-of-their-head stupid. Someone who completely misses the point of every conversation, lacks basic social graces and behaves impulsively. They do not seem capable of rational thinking, and laugh at really dumb shit (and then have to tell you about it). You'll know a Duyuy when you see one. You might even know a couple already.
Mike: "I can't believe he brought that chocolate bar in the bathroom. Now he's licking his fingers, and I just know he didn't wash his hands again. What a duyuy"
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?"