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

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 • Jan. 14, 2026

A favourite with the bookies, the song's only Achilles heel is its similarity to last year's winner, Nemo.

From BBC • May 9, 2025

Human nature, in the end, is our Achilles heel.

From Los Angeles Times • Jan. 24, 2025

It's the Achilles heel of authoritarians throughout time.

From Salon • Nov. 15, 2024

“An Achilles heel is a weakness, and you’ve got one.”

From "The Million Dollar Shot" by Dan Gutman