look up any word, like the eiffel tower:
A Heavy Duty Booty, usually on a fit woman with tight buttocks.
Male 1: "Damn, how she get all o dat?"
Male 2: "I ain't know man, she must work out or suntin."
Male1: "Hell yeeah, she got a Tonka Donk!"
by JabbaB May 28, 2010
It is another word for Har-roop
Har-roop is acting like such a tonk-a-donk today
by brownkidsrock March 02, 2011