Darth (Earth-2356)

"Henceforth, you shall be known as Darth... Vader."

- Sheev Palpatine

Darth is a title given to certain Sith Lords which preceded either their chosen Sith name, or, in some cases, their birth name.

History
Many Sith Lords chose to add "Darth" to their name, so much so that the word is considered synonymous with the dark side of the Force in some circles. It is also taken to signify giving up one's old life, which one such example being Anakin Skywalker becoming Darth Vader. The origins of the word are uncertain, but is often thought that "Darth" is merely a contraction of the title "Dark Lord of the Sith", although there are theories that suggest a deeper interpretation.

Ancient Sith

 * Darth Bane

Modern Sith

 * Darth Atrius
 * Darth Caldoth
 * Darth Heian
 * Darth Krall
 * Darth Mortis
 * Darth Pain
 * Darth Penumbra
 * Darth Plagueis
 * Darth Sidious
 * Darth Traya
 * Darth Tyrannus
 * Darth Vader
 * Darth Wrench

Source

 * https://starwars.fandom.com/wiki/Darth/Legends.