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Synonyms

fail-safe

American  
[feyl-seyf] / ˈfeɪlˌseɪf /

adjective

  1. 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.

  2. equipped with a secondary system that insures continued operation even if the primary system fails.

  3. (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.

  4. guaranteed to work; totally reliable.

    a fail-safe recipe for a cheese soufflé.


noun

  1. (sometimes initial capital letter) the point beyond which the bombers cannot go without specific instruction; the fail-safe point.

  2. something designed to work or function automatically to prevent breakdown of a mechanism, system, or the like.

verb (used with object)

fail-safed, fail-safing
  1. to make fail-safe.

fail-safe British  

adjective

  1. designed to return to a safe condition in the event of a failure or malfunction

  2. (of a nuclear weapon) capable of being deactivated in the event of a failure or accident

  3. unlikely to fail; foolproof

"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

verb

  1. (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

Etymology

Origin of fail-safe

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Ella changed ink and words into magic. She turned that into something. Remember what Ollie said? There’s a fail-safe. We already have the door. It’s in the words from the missing pages.”

From Literature

The boats had rejected their inputs and automatically idled as a fail-safe, making them “dead” in the water.

From The Wall Street Journal

“Only the person who activated the STM can use it again. My mom has fail-safes against everything.”

From Literature

Even if you plan to be fully engaged with managing money into retirement, a financial adviser could be a fail-safe if you can no longer make sound decisions.

From The Wall Street Journal

Congress created the Insurrection Act as a fail-safe in response to armed mobs attacking their neighbors and organized militias seeking to overthrow elected officials.

From Los Angeles Times