fail-safe

1 of 2

adjective

ˈfāl-ˌsāf 

1

: incorporating some feature for automatically counteracting the effect of an anticipated possible source of failure

2

: being or relating to a safeguard that prevents continuing on a bombing mission according to a preconceived plan

3

: having no chance of failure : infallibly problem-free

the little black dress … has consistently been the fail-safe solution for night

—Vogue

fail-safe

2 of 2

noun

: a device or measure that makes something fail-safe

Synonyms

Adjective

• reliable
• surefire
• infallible

Noun

• precaution
• preventive

Examples of fail-safe in a Sentence

Adjective

flowers have been traditionally regarded as the fail-safe gift for Valentine's Day

Noun

there are so many fail-safes built into the system that a highly unlikely series of mistakes would have to be made before failure could occur

Recent Examples on the Web

Adjective

But some business owners still choose to opt in. Using E-Verify as a fail-safe tool for ensuring legal hiring seems like a no-brainer, says Chad Cline, co-owner of the Waterfront Bar & Grill in Little Italy and several other dining venues. —Lori Weisberg, San Diego Union-Tribune, 22 June 2025

So the question then becomes: Can ground verification be trusted to be absolutely fail-safe? —Wally Rippel, IEEE Spectrum, 4 Mar. 2025

Noun

The idea was to make bank oversight both stricter and more fail-safe. —Jeanna Smialek, New York Times, 21 Mar. 2023

Shop Now 10 Navy Blue In areas with strict historic guidelines, navy blue is often a fail-safe. —Elle Decor Editors, ELLE Decor, 17 Mar. 2023

Word History

First Known Use

Adjective

1931, in the meaning defined at sense 1

Noun

1975, in the meaning defined above

Rhymes for fail-safe

• unsafe
• vouchsafe
• chafe
• safe
• waif