- Electronics. pertaining to or noting a mechanism built into a system, as in an early warning system or a nuclear reactor, for insuring safety should the system fail to operate properly.
- equipped with a secondary system that insures continued operation even if the primary system fails.
- (sometimes initial capital letter) of, relating to, or designating a system of coded military controls in which bombers dispatched to a prearranged point as part of a standard operating procedure cannot advance farther without direct orders from a designated authority and cannot have the nuclear warheads they carry armed until they have passed their prearranged point.
- guaranteed to work; totally reliable: a fail-safe recipe for a cheese soufflé.
- (sometimes initial capital letter) the point beyond which the bombers cannot go without specific instruction; the fail-safe point.
- something designed to work or function automatically to prevent breakdown of a mechanism, system, or the like.
- to make fail-safe.
Origin of fail-safe
First recorded in 1945–50; apparently from verb phrase to fail safe(ly)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for fail-safe
So as we lurch toward the next “fail-safe” milestone, there must be a way out for both sides.CEO Solutions to the Shutdown
William L. McComb
October 14, 2013
For example, at Three Mile Island, a fail-safe feature actually made the meltdown worse.The Most Dangerous Substance in America May Be Fertilizer
April 19, 2013
My Social Chef recommends the perfect, fail-safe roast chicken recipe.The Perfect Roast Chicken
October 20, 2010
Internally, the communications beam to Thule Base had been interrupted; and the fail-safe had not failed-safely.Where I Wasn't Going
- designed to return to a safe condition in the event of a failure or malfunction
- (of a nuclear weapon) capable of being deactivated in the event of a failure or accident
- unlikely to fail; foolproof
- (intr) to return to a safe condition in the event of a failure or malfunction
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012