In 'The Lord of the Rings', what is the name of the ring that rules all others?

In “The Lord of the Rings,” the ring that rules all others is the One Ring.

Sauron forged the One Ring in the fires of Mount Doom during the Second Age of Middle-earth. He invested much of his power in it, allowing him to dominate the other Rings of Power and control their bearers. Its inscription, written in the Black Speech of Mordor, expresses its purpose: one ring is meant to rule the others.

The One Ring is not simply a valuable golden object. It can make its wearer invisible in the ordinary world, but it also exerts a corrupting influence and magnifies the desire for power. Sauron’s ability to return to strength depends heavily on recovering it, which drives the central quest of Tolkien’s story.

It is often confused with the broader phrase “Ring of Power.” That phrase can refer to any of the magical rings, including the One Ring, the three Elven rings, the seven Dwarf rings, and the nine rings given to Men. The canonical name of the ruling ring itself is the One Ring.