"Toska" in Russian conveys a deep, spiritual sadness for no reason.
In many languages, a single word describes a concept that might require an entire phrase in English.
Like Japanese, Russian uses a different alphabet (Cyrillic) than English and has lots of words that just don't translate.
Here are some words for which we wish there were an English equivalent:
Тоска (tas-'ka)
While this Russian word roughly translates as emotional pain or melancholy, native speakers continue to claim Americans can't possibly understand its depth. Vladimir Nabokov, the famous Russian-American author of "Lolita," put 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.
пошлость ('poshe-list)
In Anton Chekhov’s short story “A Lady With a Dog,” the heroine cries out after sex that she has become a "poshlost" woman.
"This one word encompasses triviality, vulgarity, sexual promiscuity, and a lack of spirituality," Harvard professor Svetlana Boym explains in "Common Places: Everyday Life in Russia."
From 1860 to 1960, Boym also notes, Soviet Russia embarked on a battle against this particular form of banal obscenity.
бытие ('bwi-tee-ye)
Post by themedved on /r/doesnottranslate, this Russian noun hints at hyper-consciousness or an objective and analytical mindset. Russian-to-English dictionaries might translate it as "being." While the word does stem from the Russian verb for "to be," the exact meaning contains a metaphysical property English can't relay.
Proz.com, a forum for translations, also defines the word as "enrichment of one's life."
переподвыподверт ('per-e-pod-'voy-pod-'vert)
Reddit user deffun on /r/doesnottranslate defined this noun as "to do something in a complex, incomprehensible way."
The word kind of embodies itself, as it has four prefixes including one that repeats itself twice.
беспредел (bes-pre-'del)
Posted by Reddit user Izgoy on /r/doesnottranslate, "bespredel" literally means "without limits or boundaries," as New York University Slavic professor Eliot Borenstein defined in his book, "Overkill: Sex and Violence In Contemporary Russian Popular Culture."
The word also conjures images of chaotic violence, and Google translate says it means "lawlessness." When this state is in place, an ordinary person is at the mercy of somebody behaving without regard to law or structures.