The Portuguese word "saudade" is untranslatable. It hints at melancholy, nostalgia and a sense that something is missing. The great Portuguese writer Duarte Nunes de Leão described saudade as "memory of something with a desire for it." The sentiment is so profound the Brazillians hold an official celebration, the Day of Saudade, each January 30.
Languages are enriched by adopting untranslatable words. In recent years, "hygge," the Danish word that conjures cosiness, warmth and friendship, has captured popular culture, while in the 1980s, Japanese concepts like "kaizen" — the art of constant improvement through small changes — caught on worldwide.