There are words that are used differently in North Korea and South Korea, but even within South Korean Korean, the sentence endings, vocabulary, and phrasing you should use can change a lot depending on the situation. The basic structure may be similar, but small differences matter.
Vocabulary changes depending on context, relationship, social distance, age, and whether the situation is public or private. North Korean speech is often more direct, but in South Korea, especially in more formal or higher-status social settings, speaking that directly can make a person sound crude or unsophisticated. Formal South Korean speech is often based on cushioning expressions. So even with the same Korean writing system, the rules for using sentences differ slightly.
This is something I feel even more strongly as a non-Western speaker participating on HN. If I do not use AI translation, many of my expressions become awkward. But after asking about it, I understand that even if the original Korean text was written without AI, using AI translation alone may cause the English version to be treated as Gen AI, which means I cannot really submit my blog posts.
So, reluctantly, I write my English comments by carefully combining machine translation, the English I have learned, and manual correction. Reading this article made me worry about how low-quality or awkward my comments may appear on HN.
And I'll bet that "Modern slang expressions — enthusiastically adopted by younger generations" is also difficult for elderly South Koreans; just as teenage British slang is foreign to this seventy year old Briton.
I suspect that a kind of class distinction and lack of shared recent history is behind most of the difficulty in socialisation rather then the language itself.
This is tangential to the topic at hand, but as a Korean learner of ~9 years, it's maddening just how many English loanwords there are. In addition to pure Korean words, there's a surfeit of Sino-Korean (Chinese-derived), or Hanja words. Both of these are beautiful, and then the English loanwords stick out like a sore thumb.
It's trendy to do so, but I think displacing Korean/Sino-Korean vocabulary at this pace is reckless. I think of it as 사대주의 (toadyism) to some degree as well.
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Some years ago, I went to some cafe and ordered a coffee, like I've done thousands of times here. The employee asked me if I wanted a '디씨' (di-ssi). I had no idea what that was, so I had to ask, and lo and behold: it was shorthand for discount. Discount would be 5 syllables in Korean (디스카운트), an unbelievably long word in a language where most words are 2 syllables.
I was, and am, baffled because Korean already has a serviceable and widely used word that means discount: 할인 (hal-een), which is Sino-Korean (Hanja: 割引). I figure this is some marketing thing, but the same point applies. There are many cases where there's a perfectly capable word that, for seemingly no reason, gets switched out for an English loanword.
Maybe it's to give headaches to anyone trying to learn the language.
As someone with a degree in linguistics, I question whether the author of this article has a sufficient grasp on the subject to put it in proper context.
One of the clearest indications of a superficial understanding of the subject matter is in the section describing "words with different meaning but the same spelling" or "homophones." The examples given are word pairs like "service" and "volunteers," which are obviously related in meaning; these are what linguists would immediately identify as examples of semantic shift (or perhaps polysemy), not of homophony.
Basically every language with more than a few thousand speakers in close proximity has internal dialectical differences. Americans and Brits experience linguistic difficulties similar to what's described in the article ("nappy"…?) when newly-exposed to each others' English. Having lived in various parts of the US and Canada, I know that the same thing happens even among people without easily distinguishable accents.
Judgments and assumptions about other subgroups’ use of language is also pretty universal. Stereotypical Southern accents are often perceived as uneducated in the northeast and west of the US; Québec French is perceived as degraded by the influence of English in France, although in some ways it's extremely conservative (in the linguistic sense) and retains words and other features of 18th-century French.
Anyway, this is all to say that the article is interesting, but the linguistic barriers it describes are unsurprising and not in any way unique to Korea. Without a more informed take on the subject, I'm skeptical that language differences are such a huge barrier to integration of North Koreans into SK society, any more than a British or Australian is Nigerian accent is a barrier to integration into (say) Seattle or Vancouver.
Móvil/Celular -cell phone-
Camarero/Mesero -waiter-
Tiroteo/Balacera -shooting-
Nevera/Heladera -freezer-
Cacahuete/Maní -peanut-
Coche/Carro -car- (In Iberian Spanish carro it's a old carriage)
Ordenador/Computadora (Computador was used in Ib. Spa. long ago maybe in 1960's and 1970's). And -computación (computing) it's used on formal, academical contexts, such as papers for the university.
Of course a formally written book will be understood everywhere, and the older, the better.