fail-safe

[ feyl-seyf ]

/ ˈfeɪlˌseɪf /

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See synonyms for fail-safe on Thesaurus.com

adjective

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.

noun

(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.

verb (used with object), fail-safed, fail-saf·ing.

to make fail-safe.

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Origin of fail-safe

First recorded in 1945–50; apparently from verb phrase to fail safe(ly)

Words nearby fail-safe

failed, failed star, failed state, failing, faille, fail-safe, fail-soft, failure, fain, fainaigue, fainéant

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use fail-safe in a sentence

The Big Five banks dubbed too big to fail, are 35 percent bigger than they were when the meltdown was triggered.
Sen. Warren’s Main Street Crusade to Pressure Clinton|Eleanor Clift|January 8, 2015|DAILY BEAST
And it must make sure that the platform of debate where we can freely exchange ideas is safe and sound.
Ayaan Hirsi Ali: Our Duty Is to Keep Charlie Hebdo Alive|Ayaan Hirsi Ali|January 8, 2015|DAILY BEAST
They called for peace, reconciliation, and the safe return of Father Gregorio.
Mexico’s Priests Are Marked for Murder|Jason McGahan|January 7, 2015|DAILY BEAST
Their leader, Njie, still going by “Dave” during the operation, would stay a safe distance away until the State House was secure.
The Shadowy U.S. Veteran Who Tried to Overthrow a Country|Jacob Siegel|January 6, 2015|DAILY BEAST

Diets not only fail to make us thinner, they also fail to make us healthier in the long term.
Why Your New Year’s Diet Will Fail|Carrie Arnold|December 30, 2014|DAILY BEAST
A desultory conversation on politics, in which neither took the slightest interest, was a safe neutral ground.
The Pit Town Coronet, Volume I (of 3)|Charles James Wills
The governor of the fortress was provided with a safe residence in Egypt, and an annual pension of 75,000 piasters.
The Every Day Book of History and Chronology|Joel Munsell
Could this be the safe old house in which childish days had passed, in which all around were always friendly and familiar faces?
Checkmate|Joseph Sheridan Le Fanu
It would make everyone careful, of course, but I fail to see any grievance in that.
The Salvaging Of Civilisation|H. G. (Herbert George) Wells
The truth is, it is not safe to trot down such mountains and hardly to ride down them at all.
Glances at Europe|Horace Greeley

British Dictionary definitions for fail-safe

fail-safe

adjective

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

verb

(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

fail-safe

Origin of fail-safe

Words nearby fail-safe

Words related to fail-safe

How to use fail-safe in a sentence

British Dictionary definitions for fail-safe