Eru Ilúvatar
Eru is introduced in "The Silmarillion" as the supreme being of the universe, creator of all existence. In Tolkien's invented Elvish language Quenya, "Eru" means "The One", or "He that is Alone" and "Ilúvatar" signifies "Allfather". The names appear in Tolkien's work both in isolation and paired ("Eru Ilúvatar").