一切經音義 23.29

23.29

或級其頭（漢書衛青霍去病傳第二十五云斬首三千一十七級顏師古曰本以斬敵一首拜爵一級故即因謂斬首為級亦即又名生獲一人為一級也珠叢曰斬首一名為級也）。

"Or decapitating their heads" (The twenty-fifth treatise, the "Biographies of Wei Qing and Huo Qubing" in the Hanshu, says: "Beheaded three thousand and seventeen ranks." Yan Shigu says: "Originally, one rank of nobility was conferred for severing one enemy head; hence, severing a head came to be called a 'rank' [級]. Capturing one person alive was also termed a 'rank.'" The Zhucong says: "Severing a head is also called a 'rank'").