The art of being chic, amusing, or fashionable by literally having the cahones or reputation enabling you to get away with doing precisely the opposite.
So unfashionable it is awesome.
Alternate definition: Appreciation or disgust for someone so completely out of tune with societal norms, taste, or taboos. So horribly unfashionable it is like... wow.
(alternate definition) Photos of david hasselhoff with a shirt open too much, showing off his chest hair might be simply disturbing to someone in the states. (Primary definition) Despite his poor taste in Germany he is the shit!
Wearing a tropical shirt and shorts in the middle of winter can be plab.