徹 penetrate, clear, pierce, strike home, sit up (all night) 15 strokes jōyō, taught in secondary school old JLPT 1 #968 in newspapers Readings Onテツ In Chinese 彻, traditional 徹 Words written with it 徹底 てってい thoroughness N3 徹夜 てつや staying up all night N3 徹する てっする to penetrate N1 徹底的 てっていてき thorough 冷徹 れいてつ cool-headed 不徹底 ふてってい inconsistent 一徹 いってつ obstinate 貫徹 かんてつ accomplishment 透徹 とうてつ transparency