A name given to a person who has ears that stick out the side (at a greater angle than is usual) like little wings on their head. Sort of reminiscent of those little nuts that are easy to screw because of their wing-like attatchments, also called "wing nuts".
This is how it is used by some people in New Zealand anyway.
An eccentric who is usually driven by religious fever. They will take irrational social or political positions and not care that people will think that they are off balance. Being extreme somehow substantiates their faith.