The kanji 研 primarily conveys the meaning of "to grind," "to polish," or "to study/research." It suggests a process of refining, improving, or delving deeply into a subject. It implies a process of removing imperfections or gaining knowledge through focused effort.

・On-yomi (音読み): ・ケン 研 ・Kun-yomi (訓読み): ・と-ぐ 研 (to sharpen, to grind)

⚫︎研究（けんきゅう） Translation: Research; study ⚫︎研磨（けんま） Translation: Polishing; grinding ⚫︎研修（けんしゅう） Translation: Training; study

The kanji 研 is a phono-semantic compound (形声文字). The left side is the radical 石 (いし) which means "stone." The right side is a phonetic component, meaning its original sound. The original meaning of 石 implies that the characters relate to the concept of grinding or sharpening stone, and by extension, refining something or studying something deeply. Over time, the meaning expanded to encompass the broader concept of study and research.