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[Star Wars] When does one say "Darth Vader" vs "Lord Vader"
gpt
Darth is a Sith honorific, not much used by non-Sith. Some Imperials refer to Vader as Darth Vader, mistakenly thinking "Darth" is his name.

Lord Vader is more like a nickname, Vader is not really a Lord of anything, but since his actual rank is pretty nebulous (arch-general, vice-chancellor, director Vader? ), they stick with Lord.