Niflheim, also called Niflheimr, is a location in Norse Mythology meaning "mist world". In the story of Gylfaginning, Odin explains that creation began when the ice of Niflheimr met the flames of Muspelheim. Nibelheim is literally translated as "fog-home" in German. "Nibel" is an old-fashioned way to pronounce "Nebel", the German word for "fog", but can also be translated as "cloud" resulting in "cloud home".
See Special:Whatlinkshere/Etymology:Niflheim for a list of articles using this term.