Achilles heel

American  

Or Achilles' heel

noun

1. a portion, spot, area, or the like, that is especially or solely vulnerable.

   His Achilles heel is his quick temper.

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Achilles heel British  

noun

1. a small but fatal weakness

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Achilles' heel Cultural  

1. A point of vulnerability. (See Achilles.)

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Achilles' heel Idioms  

1. 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]

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Etymology

Origin of Achilles heel

First recorded in 1800–10

Example Sentences

Gauff's serve has been her Achilles' heel in recent times, but she had few issues with it initially.

From Barron's

But Gauff's serve is her Achilles' heel and she double-faulted twice in her opening service game to gift the 24-year-old Baptiste the break back.

From Barron's

Also, European investors’ accumulation of U.S. assets over the past 15 years is not necessarily “the Achilles’ heel of the dollar,” in their view.

From MarketWatch

CEO succession has long been Disney’s Achilles’ heel.

From Los Angeles Times

Even China’s imports of crude, previously an Achilles heel given its heavy dependence on energy to fuel its economy, dropped 8.8% as electric vehicles continue to dominate the market for autos domestically.

From MarketWatch