Someone who still beleives the world is flat, even the overwhelming evidence that says it's not won't sway them. Apparently it's a government conspiracy
"The world is flat , the govement is hiding this fact because they don't want us to know about the richgold deposits outside the known map"
1. The state of being a flattard.
2. An insult to one's intelligence.
The word flattarded originates from the derogatory name for people who believe the Earth is flat, or "flattards". Flattarded is used as an alternative to the popular insult "retarded" and is generally considered to be more derogatory in nature.
John: "I can't believe you think the Earth is a globe it's obviously flat!"
Bill: "Fucks sake John I didn't know you were this flattarded."