Achilles' heel

/əˌkɪliːz ˈhiːl/

a fatal weakness despite overall strength

Achilles' heel in a sentence

“His temper was his Achilles' heel.”

From Achilles, invulnerable except where his mother held him when dipping in the Styx

Related Words

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requiring tremendous strength or effort

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daringly creative or innovative, often at great risk

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a long, eventful journey or experience

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something that appears benign but contains hidden danger

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the ability to make money from anything

Narcissism

excessive self-love and admiration