mingtard
Quite simply a mixture of a minger (someone who fell out of the butt ugly tree and hit the sphincter on the way down) and a fucktard (someone who isn't retarded, but who is so stupid/annoying/idiotic, that they sure do appear that way.)
Not only was that barmaid as fat an ugly as a hippo, she couldn't even subtract 4 from 10. What a mingtard!