I always got the impression that it was more of an colloquialism as opposed to an official label.
That’s what it should’ve been, but it always was something of an official label. There’ve been self-described dark Jedi, and most sources capitalize the “D” in “dark”.
I prefer “fallen Jedi” as a term for Jedi who went bad.
That sounds a little better, but doesn’t that communicate more-or-less the same idea though? Plus I don’t see why a darksider would destcribe him-/herself as being “fallen”.
Sorry. I should’ve specified that “fallen Jedi” is a term Jedi themselves would use. I imagine darksiders would identify as ex-Jedi, or even continuing identifying as adjectiveless Jedi.
“Dark” is at least a term such a character might use with some pride
I can see more “Satanic” darksiders going that route.