My college friend Judy just posted a Facebook link to this infographic, which illustrates 11 words that have no direct, one-word translation in English. My favorite, by far, is "sobremesa" - a Spanish word for "the time spent after lunch or dinner talking to the people you shared the meal with."
In other words, my very favorite activity. I always just called it "sitting around at the table after dinner, drinking wine and talking."
But as a great lover of efficiency, I'm all for one word. And all for sobremesa.