The name Fenrir is a boy's name meaning "fen-dweller". Fenrir and is often added to lists like Names That Mean Moon.
From the experts:
The name of a monstrous wolf in Norse legend, who kills the god Odin and is then killed himself by one of Odin’s sons. Harry Potter author J.K. Rowling used the name for one of her most terrifying characters: the evil werewolf Fenrir Greyback.