Hiddensee.
I don't know what this name means, but the original meaning is very likely completely lost.
Hiddensee is a small island in the east-north of Germany.
You as English-speaking persons would translate it like "hidden - seeing" or so, but "see" means "lake" or "sea" in German. The word "hidden" does not exist in the German language.
So an Island with the name "hidden lake" ? <img src="/ubbthreads/images/graemlins/delight.gif" alt="" /> No, the original meaning is unreachable for me. I guess the original name sounded quite differently, but became distorted through the work of centuries.
Another explanation is that the word was originally a name from the language of the "Pommern", people who lived there, and that was a language close to the Polish language, because the ancestors of the people of Polen of today lived in that area, too.