In reference to several threads recently active here:
At what point does one have to resort to using an original language because English (or German, French, whatever) doesn't "properly carry its connotations"?
Examples we often see of people using original languages instead of an English equivalent include the endless debate about Theotokos vs. "Mother of God." Or the insistence on saying "theologoumena" rather than "pious opinion," Prelest vs. "spiritual delusion," Kenosis vs "emptying", etc.?
These, of course, are not words that would stand out for those more learned than I, just the ones that I thought of just now.
So, are there Orthodox words that one must use because they don't have an equivalent? And if they don't have an equivalent, how does one explain the concept?