고(高): One Hanja Root, Ten Korean Words
Written and reviewed by Jun and Jin, native Korean speakers
Published · Updated · How we write & review
After this page, you can recognize the 고(高) root and guess the meaning of new words built from it.
10-second answer
The short answer
고 (go) comes from 高, meaning "high" or "tall." It shows up wherever Korean talks about degree, level, or intensity being high: 고속 (gosok, high speed), 고온 (go-on, high temperature), 최고 (choego, the highest, "the best"), 고급 (gogeup, high-grade, upscale). Its direct opposite is 저(低) (jeo) — "low" — and the two roots pair up constantly (고온/저온, go-on/jeo-on; 고급/저급, gogeup/jeogeup), which makes them worth learning together.
Quick check — did that land?
1. What does 최고 mean?
고온, 고급, 고속. Think it means high every time?
Words Built on 고(高)
| Word | Breakdown | Meaning |
|---|---|---|
| 최고 (choego) | 최(most) + 고(high) | The highest; "the best" — Korea's default word for "awesome" |
| 고속 (gosok) | 고(high) + 속(speed) | High speed — 고속도로 (highway/expressway) |
| 고온 (goon) | 고(high) + 온(temperature) | High temperature |
| 고급 (gogeup) | 고(high) + 급(grade/rank) | High-grade, upscale, premium |
| 고혈압 (gohyeorap) | 고(high) + 혈압(blood pressure) | High blood pressure — the opposite of 저혈압 |
| 고향 (gohyang) | 고(old, a different character: 故) + 향(home village) | Hometown — not the 高 character, but easy to confuse by sound |
| 고층 (gocheung) | 고(high) + 층(floor) | High-rise, high floor of a building |
| 고백 (gobaek) | 고(reveal, a different 告) + 백(state) | A confession — the K-drama word for confessing feelings (not the 高 character, but easily confused by sound alone) |
| 고등학교 (godeunghakgyo) | 고등(high level) + 학교(school) | High school |
| 고가 (goga) | 고(high) + 가(price) | High-priced, expensive |
Watch for the sound-alike trap
Not every 고 is 高 — 고백 (confession) uses a different character (告, "to tell/declare") that just happens to share the sound. When a word is clearly about elevation, speed, price, or grade, it's almost certainly 高; when it's about telling, declaring, or an old/past sense, it's a different root.
See also: 학(學): One Hanja Root, Ten Korean Words
고 vs 저 — Learn the Pair
| 고 (high) | 저 (low) | Meaning pair |
|---|---|---|
| 고온 (high temperature) | 저온 (low temperature) | Used on packaging, weather reports, appliance settings |
| 고급 (high-grade) | 저급 (low-grade) | Product and service quality |
| 고속 (high speed) | 저속 (low speed) | Traffic, machinery, internet |
| 고가 (expensive) | 저가 (cheap) | Pricing — 저가 항공 (low-cost airline) |
Once 고 and 저 click as opposites, you can decode compound words on sight — see 저(低) for the full mirror list, the same trick used for 학(學) and 전(電).
Quick Examples
이 가방 진짜 고급스러워 보여요.
i gabang jinjja gogeupseureowo boyeoyo.
This bag looks really high-end.
고급스럽다 — "to look/feel upscale," built directly from 고급.
할아버지가 고혈압이 있으세요.
harabeojiga gohyeorabi isseuseyo.
My grandfather has high blood pressure.
고혈압 — 고(high) + 혈압(blood pressure). Its opposite is 저혈압 (jeohyeorap).
고속도로가 많이 막혀요.
gosokdoroga mani makyeoyo.
The highway is really backed up.
고속도로 — 고속(high speed) + 도로(road).
Common Mistakes
Mistake #1 — Assuming every 고 means "high"
고백 (confession, 告), 고향 (hometown, 故), 고민 (worry, 苦) and a few others come from different characters. Let context (elevation/speed/price/grade vs. telling/origin) be the guide.
Mistake #2 — Missing the 고/저 pairing
Products, weather, and settings constantly use 고/저 as a pair (고온/저온 on a washing machine dial). Spotting one half tells you the other exists.
Mini Quiz
2. What is 고혈압?
3. Which word does NOT use the 高 (high) character?
Related Knowledge
Learn Next
저(低): One Hanja Root, Ten Korean Words
고 and 저 are learned as a pair — see the opposite root next while the comparison is fresh.
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