Some historians suggest that "Darth" is actually a corruption of the Rakatan word Daritha, meaning "emperor". Others note another Rakatan connection: the words for "triumph" or "conquest" in Rakatan is darr, and the word for "death" is tah, leading to the theory that "Darth" is derived from darr tah and therefore means "triumph over death" or "immortal". Given the Sith obsession with discovering the means to achieve immortality, this idea is not entirely without merit, at least on the surface. But others point out that the true meaning of darr tah is "conquest through death," meaning the conquest of one's enemies.
Ultimately, the flaw in such theories involving a Rakatan origin is that, even if they are accurate, they cannot spring specifically from Revan or Malak's re-discovery of the Rakata and the Star Forge. Five years prior to their emergence as Sith Lords (3964 BBY), the title "Darth" was already well known by the Jedi in connection to the Sith, which is why Padawan Zayne Carrick could call Jarael "Darth Sunshine". In addition, Haazen claimed that if he were to take a name like the Sith of old, it would be "Darth Hayze," all but asserting that the title Darth was around prior to Revan and Malak's discovery. There is still the possibility that one of the Rakatan theories could be correct, since the ancient Sith homeworld of Korriban had once been occupied by the Rakata (circa 28,000 BBY), which is one way either the Daritha or darr tah term could have entered the ancient Sith language. Darth Andeddu lived during the time of the old Sith Empire (6900 BBY to 5000 BBY), early enough for his holocron to come into the possession of the fallen Jedi Freedon Nadd. He was known for experiments into eternal life, a possible link to the Rakatan term.
But even if the Rakatan connection proves to have some validity, numerous other cultures make similar claims to the etymology of the title, so for the present, there is no definitive answer as to what the term "Darth" truly means.
Usage of the term
"Someone here once told me that the Darth title was no longer used because it promoted rivalry among the Sith. It gave the Jedi an easy target. It was easier just to abandon the custom. To have all the Sith Masters use the same title of Dark Lord. But I know the truth, Qordis. I know why none of you claim that name for yourself. Fear. You're cowards. None of the Brotherhood is worthy of the Darth title. Least of all you." ―Darth Bane[src]
The earliest use of the title that can be pinned down to a specific year was by Naga Sadow, last of the original Dark Lords of the Sith that ruled the old Sith Empire. The expatriate Lord Vitiate renewed usage of the title in his reformed Empire. There, the "Darth" title was used by high-ranking Sith Lords, including members of the Dark Council. Later Sith Lords of the Jedi Civil War era also used the title Darth, as did the founding Sith Lord of the Light and Darkness War, Darth Ruin, though there were few later Sith bearing the title until the rise of Darth Rivan and Darth Bane. During the Draggulch Period, Lord Kaan discouraged the usage of the term within the Brotherhood of Darkness, claiming that it promoted rivalry among the Sith. Darth Bane, believing that the reason was merely fear, revived the use of the title in the last days of the Brotherhood. Bane, as the only survivor of the Sith Order after the Seventh Battle of Ruusan, was largely able to reshape the Sith in his own image, instituting such reforms as the Sith of his lineage adopted the Darth title as he did, generally coupling it with a new Sith name (e.g. Sidious, Tyranus, Vader), which appears to have been chosen for the apprentice by the master at the time the apprentice swore allegiance to the Sith. Not all usages of the term "Darth" during this time, however, preceded a Sith name, as Darth Maul's name had the title of "Darth" preceding his birth name.
By the time of the One Sith, the "Darth" title was reserved only for those who proved their power and their unquestioning loyalty to Darth Krayt. Others, such as Vul Isen, were not entitled to the Darth title despite their expertise in the Dark Side of the Force, and weren't regarded as "real" Sith by some of the Darths.
