Meaning & readings

polish, study of, sharpen

On’yomi ケン
Kun’yomi と.ぐ
Nanori のり

Origin

This character combines stone () on the left, which indicates the general category of working with hard materials, with a sound component (开) on the right that hints at the pronunciation. The stone radical makes sense because the character's original meaning was to sharpen or polish stones and tools by grinding them together. Over time, the meaning expanded from this physical action to the more abstract sense of studying or refining knowledge—just as you polish a stone to make it smooth and useful, you polish your mind through study.

AI-generated (claude-haiku-4-5), not yet reviewed. Formation type (automated guess): Phono-semantic (meaning + sound hint).

9 strokes

Components

  • radical left
  • sound hint right

A sound hint component points at the character’s pronunciation, not its meaning — don’t read a meaning into it.

Common words

  • 研究 けんきゅう research; study
  • 研修 けんしゅう training (esp. in-service); induction course
  • 研磨 けんま grinding; polishing
  • 研ぐ とぐ to sharpen; to hone
  • 研究員 けんきゅういん researcher; lab worker
  • 研究室 けんきゅうしつ laboratory
  • 研究者 けんきゅうしゃ researcher
  • 研究所 けんきゅうじょ research institute; (research) laboratory

Reference

Strokes
9
Kangxi radical
112
Grade
Grade 3 (Kyōiku)
Frequency rank
#336 (newspapers)
Former JLPT
level 3
Unicode
U+07814