A translation of the Elvish name Taur-nu-Fuin, originally used in the First Age to describe the forested land of Dorthonion after it fell under the power of Morgoth and became a dark and deadly place. The name recurred in the Third Age, when the coming of Sauron to Greenwood the Great caused darkness and Shadow to spread through its trees. That forest, too, became known as Taur-nu-Fuin, though in that case it was more commonly called by the name that Men gave to the darkened forest: Mirkwood.