a matter of life and death


Also found in: Acronyms, Wikipedia.

matter of life and death

Something that is gravely serious. This top-secret project is a matter of life and death, so every bit of information in it needs to be accurate. I'm a nurse, so if I make a mistake at my job, it's a matter of life and death.
See also: and, death, life, matter, of

a matter of life and death

or

a matter of life or death

COMMON If something is a matter of life and death or a matter of life or death, it is extremely important, often because someone could die or suffer great harm if something is not done. 24-hour care can actually be a matter of life and death for premature babies. Please, keep your voice down and just do what I say. This is a matter of life or death. Note: People say that something is not a matter of life and death to say that it is not very important, especially when someone else is acting as if it is. Well, never mind, John, it's not a matter of life and death. Note: People use life-and-death before nouns to describe a situation that is extremely serious or dangerous. We're dealing with a life-and-death situation here.
See also: and, death, life, matter, of

a matter of life and death

a matter of vital importance.
See also: and, death, life, matter, of
References in classic literature ?
The thing seemed clear enough; it was a matter of life and death.
Although she would infinitely have preferred a personal interview with Noel Vanstone, there was no choice on a matter of life and death but to save the precious hours by writing to him.
I bethought me of your flimsy things,” cried Natty, throwing loose the folds of a covering buckskin that he carried on his arm, and wrapping her form in it, in such a manner as to envelop her whole person; “ now follow, for it’s a matter of life and death to us all.
My lord, it is a matter of life and death," said the priest.
He brings in his psychology, too; one has to consider him, too, for it's a matter of life and death.