look up any word, like cunt:
it derives from the urban vernacular suffix of "wack" meaning undesierable and the negro prefix of "booty" meaning foul. it means something that is worese than "wack" and as dirty as "booty"
Nigga yo bref is Bootywack.

Dat Geo wit da spinnin' hubcaps looks bootywack.
by 51L3l\l7 8U7 l)34l)Ly August 19, 2004