Listverse has had a couple posts over the past several years of words that are very difficult to translate from their native tongue.
Here are a couple of my favorites as described at Listverse....
Hygge is something we all want all the time – but seldom have. It is a Danish word meaning a “complete absence of anything annoying, irritating or emotionally overwhelming, and the presence of and pleasure from comforting, gentle and soothing things”. It is especially associated with Christmas time, grilling Danish sausage on long summer evenings and sitting around lit candles on a rainy night.
Uitwaaien: Literally, this Dutch word means to walk in the wind, but in the more figurative (and commonly used) sense, it means to take a brief break in the country side to clear one’s head. It is amazing that one word needs so many in English to make the same sense.