In Chinese martial arts, 剑 (jiàn, double-edged sword) is considered the 'gentleman of weapons' (百兵之君), associated with elegance and scholars. 刀 (dāo, single-edged blade) is the more practical battlefield weapon.
usage
Common idiom: 双刃剑 (shuāng rèn jiàn) — 'double-edged sword,' used figuratively just like in English.
