Idiom B2

By the skin of your teeth

To only just succeed or escape from danger — with the smallest possible margin.

Meaning

By the skin of your teeth — To only just succeed or escape from danger — with the smallest possible margin. If you do something by the skin of your teeth, you barely manage it; any less effort or luck and you would have failed or been caught.

Origin & Etymology

This idiom comes from one of the oldest books in the Bible. In Job 19:20, the suffering Job says: "I am escaped with the skin of my teeth." The phrase is paradoxical — teeth have no skin — which is precisely the point. The margin was so small it was almost non-existent.

The expression entered common English usage after the King James Bible (1611) and has been used figuratively ever since to describe any near-miss or barely-achieved success. The modern form shifts from "my" to "your" (or "his", "her", "their") depending on the subject.

Example Sentences

SentenceContext
She passed the driving test by the skin of her teeth — one more mistake and she would have failed.Academic / test result
The team escaped relegation by the skin of their teeth, finishing just one point above the drop zone.Sport / competition
He caught the last train by the skin of his teeth; the doors closed the second he stepped on board.Everyday near-miss
The company survived the financial crisis by the skin of its teeth, but emerged leaner and more focused.Business / formal journalism

How to Use It

Register: Informal to neutral. The idiom is common in spoken English, casual writing, and journalism, particularly when describing dramatic narrow escapes. It can appear in semi-formal contexts such as news reports or sports commentary for rhetorical effect.

When to use it: Use this idiom when the margin of success or escape was genuinely very narrow — an exam passed with the minimum grade, a deadline met at the last second, or an accident narrowly avoided. It conveys relief as well as surprise.

When not to use it: Do not use it when someone succeeded comfortably — that would misuse the idiom. Also avoid it in formal academic writing, legal documents, or official reports, where plain language is expected.

Common Mistakes

Mistakes to Avoid

He won the race by the skin of his teeth with a huge lead.

He won the race by the skin of his teeth, crossing the line just ahead of his rival. — The idiom requires a genuinely narrow margin.

She passed by the skin of her tooth.

She passed by the skin of her teeth. — The noun is always plural: teeth, never tooth.

I escaped the skin of my teeth from the fire.

I escaped the fire by the skin of my teeth. — The full fixed phrase is by the skin of [possessive] teeth; do not rearrange it.

Related Idioms

A close call In the nick of time Under the wire A narrow escape Bite the bullet All Idioms →

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Frequently Asked Questions

What does "By the skin of your teeth" mean?
"By the skin of your teeth" means to only just succeed or escape from danger — with the smallest possible margin. It describes a very narrow success or escape where almost anything could have gone differently.
Where does the idiom "By the skin of your teeth" come from?
The phrase comes from the Book of Job in the Bible. In Job 19:20, Job says: "I am escaped with the skin of my teeth." The phrase suggests that teeth have no skin at all, so escaping by that margin means escaping by virtually nothing. The King James Bible (1611) brought it into widespread English use.
Can you give an example of "By the skin of your teeth" in a sentence?
Here is an example: "She passed the driving test by the skin of her teeth — one more mistake and she would have failed." This shows how narrow the margin of success was.
Is "By the skin of your teeth" formal or informal?
This idiom is mostly informal to neutral. It is common in spoken English and informal writing such as emails or social media. It can occasionally appear in journalistic writing for dramatic effect, but avoid it in formal academic or business documents.
What CEFR level is "By the skin of your teeth"?
This idiom is typically taught at B2 level. It is an upper-intermediate expression that appears in a wide range of spoken and written English contexts, including news, fiction, and everyday conversation.
What are common mistakes with "By the skin of your teeth"?
A common mistake is using the singular "tooth" instead of the plural "teeth" — always say "by the skin of your teeth". Another error is applying the idiom to situations where the margin was not actually narrow. The idiom only works when success or escape was barely achieved.
What idioms are similar to "By the skin of your teeth"?
Similar idioms include: a close call, a narrow escape, just in the nick of time, scrape through, and under the wire. These all describe situations where something was achieved or avoided with very little margin to spare.
How do I practise idioms like "By the skin of your teeth"?
LexFizz's Quiz, True or False, and Matching Pairs exercises are great for practising English idioms. Try to write your own example sentences using the idiom in context, and listen for it in films, podcasts, and everyday conversations.
Can "By the skin of your teeth" be used in writing?
Yes, but with care. It works well in informal writing, personal narratives, and journalism. Avoid it in formal academic essays, legal documents, or official business correspondence, where plain language is preferred.
Does "By the skin of your teeth" have the same meaning in British and American English?
Yes, "by the skin of your teeth" is understood in both British and American English with the same meaning: barely succeeding or escaping. The biblical origin means it has been part of English for centuries and is recognised across all major varieties of the language.