By Daniel, ESL Educator & Idiom Series Author
Here’s a fair question for any English learner to ask: teeth don’t have skin, so what does by the skin of your teeth mean?
It’s a better question than it sounds. And the honest answer is that even experts aren’t completely sure what the original words meant. But the modern meaning is very clear.
The meaning: you made it, but only just
If you do something by the skin of your teeth, you succeed or escape, but by a very small margin. A little less, and you would have failed.
- “I passed the driving test by the skin of my teeth.” (I passed, but barely.)
- “We caught the last train by the skin of our teeth.” (The doors were closing.)
A phrase from an old translation
This idiom comes from the Bible, from the Book of Job. Job is a man who loses almost everything: his family, his wealth and his health. In chapter 19, verse 20, he describes how thin and sick he has become.
According to David Wilton of Wordorigins.org, the phrase first appeared in English in the Geneva Bible of 1560: “I haue escaped with the skinne of my tethe.” The King James Version of 1611 repeated it as “I am escaped with the skin of my teeth,” and that famous translation helped make it a common English expression.
Notice two things:
- The original preposition was “with,” not “by.” Modern English changed it.
- The original meaning is uncertain. Pascal Tréguer of Word Histories explains that scholars still debate what the Hebrew words meant. The “skin” might be the gums, or the hard surface of the teeth. Some modern commentators think Job wasn’t talking about a narrow escape at all, but saying something closer to “I have lost everything.” Other old translations were quite different. One early English Bible, following the Latin, said that only his lips were left around his teeth.
So the meaning we use today grew out of the English wording more than out of the original text. That happens with idioms more often than you might think.
The detail that trips people up
The idiom is about a narrow success, not a failure. That’s the key point many learners miss.
❌ “I failed the exam by the skin of my teeth.”
✅ “I failed the exam by just two points.” / “I nearly passed.”
✅ “I passed the exam by the skin of my teeth.”
Also notice that the phrase usually describes something that already happened. People look back and feel relief: “Wow, we made it, but only just.” It sounds strange to plan for it: “I hope to pass by the skin of my teeth” is unusual unless you’re joking about low expectations.
Grammar you need
- Change the possessive to match the person: by the skin of my / your / his / her / our / their teeth.
- Keep “teeth” plural, even for one person.
- Common verbs before it: pass, escape, survive, win, make it, catch, get through.
- Tone: informal to neutral. It’s fine in conversation and in most writing, but in a formal report, “narrowly” is a safer choice.
At the airport
Priya: Did you make your connecting flight in Frankfurt?
Tom: By the skin of my teeth. The first flight landed late, and I ran the whole way.
Priya: And your bag?
Tom: My bag was not so lucky. It arrived two days later.
Close relatives
- barely / just: the simple everyday words: “We just made it.”
- a close call: a situation where something bad almost happened: “That car nearly hit us. That was a close call.”
- a narrow escape: a near-disaster that you avoided, a little more formal
- down to the wire: when the result isn’t decided until the very last moment
Rewrite it
Rewrite each sentence using by the skin of … teeth.
- Nina barely finished the marathon before the time limit.
- Our team just won the final, 2–1, in extra time.
Answers: 1. Nina finished the marathon by the skin of her teeth. 2. Our team won the final by the skin of our teeth.
You might also like: Down to the Wire, for close finishes of another kind.
A Note from Daniel
What I find interesting about this idiom is how it has traveled from one of the oldest books in the Bible, through centuries of literature and religion, to our everyday conversations about things like test scores or missed flights. At first, it described a kind of suffering that was hard to explain, but over time, it came to mean those close calls we all know. This journey shows how much that feeling—a combination of relief and amazement—connects with people in different times and situations. If you have a story about a time you made it by the skin of your teeth, I’d love to hear it.
Sources
- Wilton, D. “Skin of one’s teeth.” Wordorigins.org. wordorigins.org
- Tréguer, P. “The uncertain biblical meaning of ‘by the skin of one’s teeth.’” Word Histories, 2017. wordhistories.net
- Cambridge Dictionary, entry: “by the skin of your teeth.”
Every word carries a story. Stay curious. — Daniel