a matter of life and death
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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.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
a matter of life and deathor
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.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
a matter of life and deatha matter of vital importance.
Farlex Partner Idioms Dictionary © Farlex 2017
matter of life and death, a
An issue of vital importance. This term, used since the mid-nineteenth century, makes more sense as a matter of life or death, and indeed it sometimes is so used. An 1837 letter of Dickens states, “It is matter of life or death to us, to know whether you have got Ainsworth’s MS yet.” However, a life-and-death matter appears with equal frequency.
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer