Achilles heel

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Achilles heel (metaphor)
/əˈkɪliːz hiːl/

Meanings

• A hidden weakness or vulnerable point that can cause failure.
• A small but critical flaw in something otherwise strong.
• A personal weakness that makes someone easy to defeat or harm.
• On the human body, the Achilles’ heel is the tendon at the back of the ankle. (literal meaning)

Synonyms: weak point; vulnerability; weak spot; flaw; shortcoming; chink in the armor; soft spot.

Example Sentences

1. His lack of patience became his Achilles heel, ruining important negotiations.
2. The software looked perfect, but security issues were its Achilles heel.
3. Her fear of criticism remained her Achilles heel, limiting her confidence.

Etymology and Origin

Mythological Foundations

The story of Achilles’ heel traces back to ancient Greek legends about the great warrior of the Trojan War. According to one popular tale, his mother Thetis tried to protect her infant son by dipping him in the River Styx, whose waters were said to grant immortality. She held him tightly by one heel, so that single spot stayed untouched by the magic and remained mortal. Years later, an arrow struck there during battle, ending his life. This vulnerability became the heart of the famous weakness we still talk about today.

Later Developments in the Legend

The full account of the river dip and the exact heel wound actually came along after Homer’s Iliad, which never mentions Achilles being nearly invincible or dying that way. Early artworks from around the sixth century BC sometimes show an arrow hitting his ankle instead. Writers in Roman times, like the poet Statius in the first century AD, helped shape the version we know best, turning a heroic flaw into a lasting symbol of hidden weakness. Different retellings over centuries added details, but the core idea stayed the same: even the strongest have one fatal spot.

Connection to Anatomy

Long before the idiom caught on, people borrowed Achilles’ name for something very real in the human body. In 1693, a Flemish doctor named Philip Verheyen described the thick tendon running down the back of the calf to the heel as the “cord of Achilles” in his book on human anatomy. He chose the name because an injury there could cripple even the toughest fighter, just like the myth. This scientific link quietly kept the hero’s story alive in everyday language.

Birth of the Idiom in English

The phrase “Achilles’ heel” as a way to describe any serious weakness in something otherwise strong first took root in England. British writers began using it metaphorically during the 1600s and early 1800s, drawing straight from the old Greek tale. It felt natural in a culture that loved classical stories, and it quickly spread as a handy way to point out a single point of failure in people, plans, or even nations. No other major explanations or rival origins have ever surfaced; the expression grew directly from that one legendary image.

Earliest Printed Record

The first clear printed example of the idiom in its metaphorical sense appears in an 1810 essay by the English poet and thinker Samuel Taylor Coleridge. In his weekly paper The Friend; a literary, moral and political weekly paper, he wrote about political matters and described Ireland as “Ireland, that vulnerable heel of the British Achilles!” This clever twist showed how the ancient myth had become a living figure of speech for a nation’s soft spot. The expression soon became common in books and conversations across Britain, marking its true start as everyday English.

Lasting Place in Language

From those early days onward, the term settled into its modern meaning without any major changes or competing stories. It reminds us that strength always comes with some risk, a simple truth that feels as fresh today as it did centuries ago. Writers, speakers, and thinkers still reach for it when they want to highlight the one flaw that could bring everything down. In the end, the idiom proves how powerfully a single old myth can shape the way we talk about life.

Variants

• the Achilles heel of something
• someone’s Achilles heel
• be an Achilles heel

Body

Last update: May 4, 2026 11:37 PM