Moving one's body in vivacious manner, such that those around you believe it to be a sincere expression of joy, but your true motivations are to sowdiscord and mock the entire event.
"Patrick had a great time at the concert last night. Did you see him dancing?"
"Nah, that was troll dancing, bruh. He hated it."
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?"