A really ugly girl, one that has the face of a rottweiler chewing a wasp. Sometimes judged by actions as well as looks. See swampdonkey.
Look at that drunk-assed girl across the bar, god what a gravel-donkey!
A girl with a face so Ugly that it looks like she has been hanging her head in shame like a donkey and it has been dragging along in the dirt!
Dammmm. Have a look at that Gravel-Donkey!!!