I so clearly remember from my days of Talmud study the phrase גלותא דגלותא, meaning a place that was REALLY far away, seriously in exile, "deep diaspora", totally removed from eretz yisrael.  Maybe it was גלותא של גלותא or גלותא שבגלותא, but I think it was galuta d'galuta.  Can anyone tell me the source for this?  I searched Sefaria and found nothing.  Thank you.