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

Once you’ve done that, you have to do it day after day to get a feel for your Achilles’ heel.

From MarketWatch

"Our patriotism was our Achilles' heel, that's what they exploited," says Mr Yu, who is in his 60s.

From BBC

But fertilizer remains Brazil’s Achilles’ heel.

From The Wall Street Journal

“UPS’s Achilles’ heel is lightweight residential packages that don’t offset the labor expense,” said Glenn Gooding, president of iDrive Logistics and a former UPS executive.

From The Wall Street Journal

The TriColor and First Brands cases prove that data integrity is the Achilles’ heel of modern lending.

From The Wall Street Journal