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

“This exposes an Achilles heel to the Burn, and other people potentially trying to get away with something this awful.”

From Salon • Oct. 27, 2025

“You have spontaneous multiple events, which is the Achilles heel of any operation,” he said.

From Los Angeles Times • Jun. 12, 2025

Before Singapore, you might have said that street circuits were Red Bull's Achilles heel, which would have led one to believe Las Vegas might be an issue for Verstappen.

From BBC • Oct. 16, 2024

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

From "The Million Dollar Shot" by Dan Gutman