Achilles’ heel

In Greek mythology, Achilles was a great warrior destined for glory. His mother, Thetis, attempted to make him immortal by dipping him in the River Styx. However, she held him by his heel, leaving that spot vulnerable. This single weakness, his "Achilles' heel," ultimately led to his death in the Trojan War when he was struck by an arrow in that spot.123

Today, the term "Achilles' heel" is used metaphorically to describe any vulnerable point or weakness, whether physical or emotional. The anatomical term "Achilles tendon" refers to the tendon connecting the calf muscles to the heel.143