Hi, Biko :) There is some info from Urban dictionary: "Bedunkadunk is a word to describe a really nice ass on a woman. It can also be used to describe a fat chick's ass, or an ass on a chubby chick. Ex. "Damn man, that chick has a bedunkadunk!" "Wow man, look at that bedunkadunk!" ;)

It can also be pronounced bedonkddonk - it means somebody's rear end - their butt.