noun -
A person far beyond retardation.
A lame idiot.
A cross between someone completely wack and someone utterly retarded.
Fool.
"I didn't know for the life of me why I couldn't sleep last night. At 3am I finally realized that I'd drank a buttload of Mountain Dew before hitting the sack. I'm such a freakin' wacktard!"
"Did you hear Lady GaGa talking about being 'celebate'? She's such a wacktard!"
"OMG, my stupid boyfriend is late again!? I can't stand his wacktarded a$$ sometimes!!!"