An extremely large ass that can't be described simply as a ba-donka-donk. Seeing one gives you an irresistible urge to say "dayummmm".
1. Ross - Check out how big Sabrina's ass is, she's got one hell of a ba-donka-donk
Me - That's no ba-donka-donk, that's a ba-donka-damn!
2. Person #1 Look how big her ass is!
Person #2 Dayuuuum...