All 3 Uses of

Achilles
in
The Hidden Oracle

I remembered Achilles falling on the plains of Troy, cut down by an unworthy archer because of my wrath.
p. 61.4 *

Achilles = mythical Greek hero of the Iliad; central character and foremost Greek warrior at the siege of Troy

It occurred to me that I'd seen that keen look in Chiron's eyes before—when he'd assessed Achilles's sword technique and Ajax's skill with a spear.
p. 106.3

I hadn't witnessed such a tense greeting since Patroclus met Achilles's war prize, Briseis.
p. 352.0

Definitions:

(1) (Achilles in Greek mythology)
mythical Greek hero of the Iliad; central character and foremost Greek warrior at the siege of Troy

Achilles was seen as semi-divine. His mother tried to make him immortal by bathing him in a magical river when he was a baby, but the heel by which she held him remained vulnerable--his "Achilles' heel."
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Achilles is also used as a shortened way to identify an achilles tendon or heel cord at the back of the lower leg.