Achilles. In Greek mythology, Achilles or Achilleus was a hero of the Trojan War, the greatest of all the Greek warriors, and is the central character of Homer's Iliad. He was the son of the Nereid Thetis and Peleus, king of Phthia. Achilles' most notable feat during the Trojan War was the slaying of the Trojan prince 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 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 one of 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. The Achilles tendon is also named after him due to these legends. The grief or distress of the people is a theme raised numerous times in the Iliad. Achilles' role as the hero of grief or distress forms an ironic juxtaposition with the conventional view of him as the hero of kleos. Furthermore, laes has been construed by Gregory Nagy, following Leonard Palmer, to mean a corps of soldiers, a muster. With this derivation, the name obtains a double meaning in the poem: when the hero is functioning rightly, his men bring distress to the enemy, but when wrongly, his men get the grief of war. The poem is in part about the misdirection of anger on the part of leadership. The shift from-dd-to-ll-is then ascribed to the passing of the name into Greek via a Pre-Greek source. The whole expression would be comparable to the Latin acupedius swift of foot. Compare also the Latin word family of acies sharp edge or point, battle line, battle, engagement, acus needle, pin, bodkin, and acuo to make pointed, sharpen, whet; to exercise; to arouse. Some researchers deem the name a loan word, possibly from a Pre-Greek language. Achilles' descent from the Nereid Thetis and a similarity of his name with those of river deities such as Acheron and Achelous have led to speculations about him being an old water divinity. Achilles was the son of the Nereid Thetis and of Peleus, the king of the Myrmidons. Zeus and Poseidon had been rivals for the hand of Thetis until Prometheus, the fore-thinker, warned Zeus of a prophecy that Thetis would bear a son greater than his father. For this reason, the two gods withdrew their pursuit, and had her wed Peleus. There is a tale which offers an alternative version of these events: In the Argonautica Zeus' sister and wife Hera alludes to Thetis' chaste resistance to the advances of Zeus, pointing out that Thetis was so loyal to Hera's marriage bond that she coolly rejected the father of gods. Thetis, although a daughter of the sea-god Nereus, was also brought up by Hera, further explaining her resistance to the advances of Zeus. Zeus was furious and decreed that she would never marry an immortal.