FOOLPROOF Synonyms: 20 Similar and Opposite Words

foolproof

adjective

Definition of foolproof

as in perfect

done, made, or planned so well that nothing can go wrong a foolproof plan DNA fingerprinting gives police a virtually foolproof way to link a suspect to a crime scene.

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of foolproof Fortunately, Jennifer Garner lent us a foolproof formula while on a recent trip with her family in Virginia. — Better Homes & Gardens, 16 July 2026 Soon enough, Karl’s seemingly foolproof blackmail scheme devolves into a merciless, dog-eat-dog fight for survival, and the two men are locked in a cutthroat collision course, their fates now inextricably linked. — Ryan Lattanzio, IndieWire, 15 July 2026 This mix of creamsicle orange and bright strawberry pink is a foolproof recipe for a delectable look. — Kara Jillian Brown, InStyle, 12 July 2026 Just pair them with a white T-shirt à la Hudson, Lawrence, and Lopez for a foolproof monochrome outfit that’ll look cute at the beach, bars, or even brunch. — Alyssa Grabinski, PEOPLE, 4 July 2026 See All Example Sentences for foolproof

Recent Examples of Synonyms for foolproof

Adjective

Their aggression on the bases wasn’t perfect — Koss and Drew Gilbert were both picked off — but the Giants have clearly made the steal more of a priority.

— Justice delos Santos, Mercury News, 28 July 2026
Beyond these coolers, there are several other styles of cooler boxes and bags perfect for a day at the beach.

— Alison Fox, Travel + Leisure, 27 July 2026

Definition of perfect

Adjective

Young was flawless until the final hole, his tee shot finding a pot bunker.

— Doug Ferguson, Los Angeles Times, 19 July 2026
The Spaniards have taken the air out of the balls, played keep-away, erected a flawless defensive fortress, and hijacked tournament brackets from far more direct teams like France and England.

— Filip Bondy, New York Daily News, 19 July 2026

Definition of flawless

Adjective

Tech firms used to be reliable stocks, reporting high profits and juicy margins, but the race to build AI data centers and train new models has changed the landscape.

— Ryan Whitwam, ArsTechnica, 23 July 2026
Digital footprint analysis is becoming one of the most reliable tools in credit risk.

— Artem Lalaiants, Forbes.com, 23 July 2026

Definition of reliable

Browse Nearby Words

foolishness

foolproof

fools

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Cite this Entry

Style

“Foolproof.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/foolproof. Accessed 29 Jul. 2026.

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Synonyms of foolproof

adjective

Example Sentences

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