Been a while since I read that series too. I stopped after Mara Jade got killed off.
Umm if you read the legacy books with Jacen Solo becoming Darth Caedus, Luyumia says it and i think the closest thing to it is "Chosen one". But it's been A LONG time since I read those books so I don't know.
Roughly translated, Sith'Ari means a few things. I believe "Chosen One" is one of them. It also means "Overlord" or just "Lord".