An Achilles' heel is a fatal weakness in overall strength that can lead to one's downfall or death.

In Greek mythology, Achilles was the greatest Greek warrior in the Trojan War. He was the son of Peleus, king of Thessaly and the goddess Thetis. When he was a baby, his mother submerged him in the River Styx to make him immortal, all except for the heel that she held to dip him into the waters.

Achilles fought many battles during the 10-year Trojan War and finally killed Memnon, the king of the Ethiopians. As Achilles led the Greeks to the walls of Troy, he died from a heel wound caused by an arrow shot by Paris, the prince of Troy.

阿喀琉斯之踵比喻致命的弱点。在希腊神话中，阿喀琉斯是色萨利密尔弥东人的国王珀琉斯和海中仙女忒提斯的儿子。在特洛伊战争中，他是阿伽门农的军队中最伟大、最勇猛的战士。阿喀琉斯一出生，她母亲就捏着他的脚后跟，把他全身都浸入冥河水中，传说冥河水可以让人永生，故而阿喀琉斯周身获得了保护，造就了一副刀枪不入的钢铁之躯，只有脚后跟除外。阿喀琉斯出征特洛伊，为希腊军队立下了巨大的功勋。后来特洛伊王子帕里斯得到神示，用毒箭射中阿喀琉斯的脚后跟，才使他丧命。