dunk'd is when you simply say something that you know will piss off your friends. then when they got all bitchy and mad, you act really sad like you hate life(act like a failure). then when they feel really bad about getting mad at you, you look up and smile say "you just been dunk'd motherfucker!" and laugh.
"John is gay"
"im not gay"
"yeah you are"
"f**k you!no im not"
"dude i was joking. sorry. i guess i'll just go."
"no man im sorry.dont go"
"No its ok man."
"well, you've just been dunk'd motherfucker"