The absolute inability to dance. Caused by the sheer act of being born 100% Caucasian. Some sufferers of TWD may show some rudimentary ability to country line dance, but will never be able to dance to any other type of music such as techno or hip-hop.
Nancy told Laura she would have to dance at the club, but Laura is too white...she has terminal white disease (TWD)and would look like a frigging idiot.
Being 100% Caucasian and performing dances like the Donkey Kong or any variety of hip-hop moves. It just doesn't work, no matter how tall you are....
(at a club) "Wow, look at that guy he's suffering from Terminal White Disease (TWD)"