Пошлый: 1) vulgar, crude; 2) a mix of pretentious, superficial, philistine, false, banal, soulless, hackneyed, mediocre, saccharine, tasteless, cliched, all served up with a fine sense of moral contempt.

      The noun пошлость and its adjective пошлый are what linguists call "key words": words that have a profound meaning for a culture and define its values. Language nuts love them for it; translators loathe them because they often have no equivalents in other languages. So what does пошлый mean? When in doubt, go back to the word's origins.  

      Пошлый, which is the participle form of the verb пойти (to go) has been used in Russian at least as far back as the 13th century. The original sense was something that had "come into existence," something customary, the way of doing things. In time it came to mean something "ancient" or "usual." When Peter the Great was cutting short beards and kaftans, what was customary (пошлый) became negative. For a while it meant "low quality" (in other words, what's old is no good). And then it came to mean something "devoid of meaning" or "trivial": meaningless custom observed by habit.

      Today пошлый is most often used in the sense of "crude" or "vulgar": пошлый анекдот (an off-color joke), пошлый намёк (innuendo) or пошлый юмор (crude humor). Пошляк in this context means a raunchy guy, a leering letch. But then there is the cosmic key meaning of пошлость, which often has nothing to do with the risque.

      Vladimir Nabokov once dedicated 11 pages to defining it, and in the end, even he, that master of words, resorted more to examples than to definitions. He preferred to transliterate what he called this "fat brute of a word" as poshlost to capture its inelegant plop and slurp -- and also, one must assume, because lust is to love as пошлость is to all that is genuine, fine, moral, beautiful and true. For as Nabokov says, пошлость is "not only the obviously trashy but also the falsely important, the falsely beautiful, the falsely clever, the falsely attractive." It's an expanded sense of "devoid of meaning": a pretense of beauty and depth without heart or soul. There isn't one word in English that captures this. Пошлость is like a fat sow dressed in a ball gown and tiara: "Trashy" gives you the dress, "saccharine" is the cute tiara, "philistine" is the snout, "pretentious" is the beribboned tail, but you still don't hear the oink or smell the pigsty.

      When translating you have to choose a meanings that best conveys the sense of пошлость in that particular context. For example, in this description of a tense dinner table conversation: Каждый чувствовал, что в подобные мгновенья позволительно сказать одну лишь пошлость, что всякое значительное, или умное, или просто задушевное слово было бы чем-то неуместным, почти ложным. (Everyone felt that in such moments it was only appropriate to say something banal, that any meaningful, or intelligent, or simply heartfelt word would have been somehow out of place, almost a lie.). You need something else in this context: Мне не нравятся его картины о сказках -- они слишком красивые, пошлые. (I don't like his paintings of fairy tales; they're prettified and precious.).

      Or here: Он интеллигентный и тонкий человек. Но его жена -- пошлая. (He's a very cultured and sensitive person. But his wife is low-rent.)

      The final element of пошлость is the implied moral censure. Pawning off pseudo for real, saccharine for sweet, trite for profound, manipulative for moving -- all that пошлость entails -- is ultimately morally wrong. And that is why foreigners fall in love with this place: because there are still folks who believe that a cheaply manipulative film, a rabble-rousing speech or a confession of love that's for show and not for real are пошлые and beneath contempt.

      My kind of folks.