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

Europe’s exposure to spot prices for liquefied natural gas is its Achilles’ heel.

From The Wall Street Journal

“These desalination plants, even more than the energy infrastructure of the Gulf monarchies, are their Achilles’ heel.”

From The Wall Street Journal

Investors and policymakers should ask themselves whether the push into the retail space may turn out to be private credit’s Achilles’ heel.

From MarketWatch

As he notes, "this same virtue had become their experimental Achilles' heel: how do you "read" or "detect" a property that doesn't reside at any specific point?"

From Science Daily

Permitting difficulties are America’s economic Achilles’ heel.

From The Wall Street Journal