Darth Vader and other iconic Sith Lords in Star Wars use the "Darth" title in their Sith monikers, but what does Darth mean, and how old is the title?

Moments before Anakin was cut down by Obi-Wan, though, something quite bizarre occurred.

Darth Sidious is one of the most well known Star ... with the most egregious being his training of Darth Maul while his own ...