DONK, What does it stand for?

I know, I know....
They have big wheels, usually 4 doors that open up not out.
Weird paint jobs with name brands of breakfast cerial, cartoons, etc...

But what the heck does "Donk" stand for besides, "I'm weird":happy10:

I must really be getting old. I don't get out much and the only way I see these is on "You drive what?" Web site. No customs round these parts like that!8)