The partial numbness of the buttocks that results from long car trips. Causes the sensation of your ass being one with the car seat. Named for the Buick line, as the suspension in these and other large sedans tends to amplify the effect.
Bob: You know, after driving for the last four hours, I feel as though I've become one with the car. Is this Zen?
Larry: Nah, it's just Buick butt.
Larry: Nah, it's just Buick butt.
by Justice Walker March 13, 2009