dur-brain 

Someone that is so dumb that all you feel like responding to them any time they speak is "dur".

You're such a dur-brain.

dur-brain by azbas May 19, 2008

Durbrain 

A common insult among 2-8 year olds, often uttered when under verbal attack or in protection of ones reputution or status.

"You're not coming to my party, You durbrain"

"Be quiet Marie, you are a durbarian"

Durbrain by Professor Chris Stark October 16, 2004