weirdo, usually. It can be a adjective or a noun. You would not want to hang around with a weiwdenz. Sometimes, if you really can't deal with a scary troll who is lurking around you, you can say to your friend, "oooh, ghoul, let's get outta here, there is a weiwdenz lurking."
Oh my gawd, that guy is weiwdener than the weiwdenest weiwdenz.