A fascinating list of the most untranslatable foreign words. In first place:
ilunga [Tshiluba word for a person who is ready to forgive any abuse for the first time; to tolerate it a second time; but never a third time. Note: Tshiluba is a Bantu language spoken in south-eastern Congo, and Zaire]
The same post includes a list of the most untranslatable English words. It includes two words that mean a load of old nonsense.