It means when you're a yoyo and your life keeps turning on you and you can never do anything about it. You live life scared, reversed, not how you would like it. I never told anyone this meaning until now... crazy how new words are created everyday. It's pronounced like, "Ded-ed-ed"
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?"