n4 Kanji
研 Kanji Meaning, Reading & Vocabulary | JLPT n4 | KanjiGym
研
Meaning : polish, sharpen, research
Onyomi :
ケン
Kunyomi :
とぐ
Examples:
研究(けんきゅう)study, research
研究室(けんきゅうしつ)laboratory