There are certain words that only exist in one language, evolved from one culture and do not translate into any other. Here is a list of some of the most interesting including my favorite, this Russian word:
Toska Russian – Vladmir Nabokov describes it best: “No single word in English renders all the shades of toska. At its deepest and most painful, it is a sensation of great spiritual anguish, often without any specific cause. At less morbid levels it is a dull ache of the soul, a longing with nothing to long for, a sick pining, a vague restlessness, mental throes, yearning. In particular cases it may be the desire for somebody of something specific, nostalgia, love-sickness. At the lowest level it grades into ennui, boredom.”
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Yacchid