| Achilles heel | |
| —n | |
| a small but fatal weakness | |
| the offspring of a zebra and a donkey. |
| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
Achilles' heel
A fatal weakness, a vulnerable area, as in This division, which is rarely profitable, is the company's Achilles' heel. The term alludes to the Greek legend about the heroic warrior Achilles whose mother tried to make him immortal by holding the infant by his heel and dipping him into the River Styx. Eventually he was killed by an arrow shot into his undipped heel. [c. 1800]