Achillean :: Achillean (a.) Resembling Achilles, the hero of the Iliad; invincible..
Achilles' Tendon :: Achilles' tendon (n.) The strong tendon formed of the united tendons of the large muscles in the calf of the leg, an inserted into the bone of the heel; -- so called from the mythological account of Achilles being held by the heel when dipped in the River Styx..