Orodruin is the Elvish name for Mount Doom in J.R.R. Tolkien’s Middle-earth.
Mount Doom is the volcano in Mordor where Sauron forged the One Ring and where it can be destroyed. The name Orodruin comes from Tolkien’s Elvish languages and is commonly translated as “Mountain of Blazing Fire.” The volcano is therefore both a geographical landmark and the central instrument of the Ring’s creation and destruction.
The mountain’s fires are connected to the power of the Ring. The Fellowship cannot destroy it by ordinary means in another place; the Ring must be returned to the Cracks of Doom within the volcano. Frodo and Sam reach the site after crossing Mordor, while Gollum ultimately causes the Ring to fall into the fire.
Amon Amarth, meaning “Mount Doom” in Sindarin, is another name for the same mountain, making the naming question potentially ambiguous in detailed Tolkien terminology. Orodruin is the canonical Quenya name, while Mount Doom is the familiar English name.