It wasn't in Prague. Not to understand me wrong, it is a normal word and an aesthetic concept only I hadn't heard it in daily conversation, then. Sabi-shii means lonely sometimes with the hidden connotation of showing rust age patina since it has a homonym written with a different character, and wabi is harder to translate but something similar like feeling lonely, deserted with a grain of longing and romance in it, I have no time to go back through the posts but I think you (?) explained it well above, anyway, something like natural simplicity but behind it a very high form of cultural development that has been 'mastered' and thereby overcome. The expression was very much influenced by Zen and also tea-masters like Sen no Rikkyu. Wabi-sabi in this form isn't or 'wasn't' -cause I'm not up to date anymore-, as such in the bigger dictionaries like the Kenkyuusha. But as an aesthetic concept every Japanese knows it, he just doesn't throw it around every day. My hometown is Vienna, btw.