expression, noun
narrow escape from death; barely escaping with one's life
Idiomatic expression used when someone survives a life-threatening situation by a very small margin. Often used with verbs like 得る (える) to mean 'have a narrow escape'.
彼はその事故で九死に一生を得た。
He narrowly escaped death in that accident.
九死に一生の思いをした。
I felt like I had barely escaped with my life.
危機一髪 also means a close call, but emphasizes the critical moment of danger, while 九死に一生 focuses on the outcome of surviving against overwhelming odds.
Literally 'one life out of nine deaths', a classical Chinese-derived expression meaning that the chance of survival was extremely slim.