Even native Korean speakers mix these up in texts because 왠 and 웬 sound very similar. 왠지 is a contraction of 왜인지, roughly “for some reason,” while 웬 is a determiner meaning something like “what kind of” or “how come this…?”
❌ COMMON MISTAKES
You may see ‘웬지 오늘 기분이 좋아’ or ‘왠일이야?’ in casual messages.
✅ STANDARD FORMS
Write ‘왠지 오늘 기분이 좋아’ and ‘웬일이야?’.
WHY THEY SPLIT
왠지 comes from 왜인지, so it keeps 왠. 웬 is a separate determiner used in phrases such as ‘웬 사람’ (what person / some unexpected person), ‘웬 소리’ and the word ‘웬일’.
A NATURAL CHAT EXAMPLE
A: 왠지 오늘 비 올 것 같아. — “For some reason, I think it’ll rain today.” B: 웬일이야? 네가 우산을 먼저 챙기고. — “What got into you? You packed an umbrella first.”
ONE SPACING DETAIL
웬 is normally separated from the noun: ‘웬 사람’, ‘웬 소리’. But ‘웬일’ is a dictionary-listed single word, so it is written together.
