Idioms are back! This week’s idiom “by the skin of one’s teeth” sounds strange but is quite common in everyday English. It means barely or by a very small margin.
For example, “I hadn’t studied much, but passed the test by the skin of my teeth.” (meaning: I barely passed the test or I almost failed the test.)
Note you can substitute any pronoun in before “teeth” (his teeth, her teeth, your teeth, etc.)
Thanks to www.myenglishteacher.eu for the picture and example.