is when a person is obviously wrong, yet refuse to accept any answer you give them despite the answer being correct. They tend to argue with you upon being corrected, and pushes you closer and closer to murder in the first degree.
"No dude, I have played Mario games on the PS2" ~AHTB
A tardnuckle is a hybrid of someone who acts retarded, and a knucklehead. Usually someone who enjoys playing retarded for fun and looks like a vacuous goon doing so.