” In Greek mythology, Achilles (/əˈkɪliːz/, uh-KILL-eez; Greek: Ἀχιλλεύς [a.kʰil.le͜ús]) was a Greek hero of the Trojan War and the central character and greatest warrior of Homer’s Iliad. His mother was the immortal nereid Thetis, and his father, the mortal Peleus, was the king of the Myrmidons.
Achilles’ most notable feat during the Trojan War was the slaying of the Trojan hero Hector outside the gates of Troy. Although the death of Achilles is not presented in the Iliad, other sources concur that he was killed near the end of the Trojan War by Paris, who shot him in the heel with an arrow. Later legends (beginning with a poem by Statius in the 1st century AD) state that Achilles was invulnerable in all of his body except for his heel because, when his mother Thetis dipped him in the river Styx as an infant, she held him by his heels. Alluding to these legends, the term “Achilles heel” has come to mean a point of weakness, especially in someone or something with an otherwise strong constitution.” https://en.wikipedia.org/wiki/Achilles