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 One foolproof way to do as the Germans do is to wear their brands. — Carolin Lehmann, Travel + Leisure, 23 Aug. 2026 Luckily, there’s a foolproof way to stay dry while looking fly — cuffed jeans. — Alyssa Grabinski, PEOPLE, 20 Aug. 2026 But, as anyone who’s watched an icy soda turn watery on a summer day can probably gather, moving hard ice to warm climates wasn’t exactly foolproof. — Mack Degeurin, Popular Science, 19 Aug. 2026 First, the cream-to-powder texture is foolproof—the edges smoke out with the slightest tap, making blending a dream. — Kiana Murden, Vogue, 17 Aug. 2026 See All Example Sentences for foolproof

Recent Examples of Synonyms for foolproof

Adjective

The shape skims one’s physique rather than hugging it, creating the kind of movement that made flapper dresses perfect for dancing.

— Corinne Pierre-Louis, Vogue, 27 Sep. 2026
Runway is a perfect metaphor for a kid who is about to take off.

— Los Angeles Times, Los Angeles Times, 27 Sep. 2026

Definition of perfect

Adjective

Exploring Ireland, one village at a time This was my first visit to Ireland, and the nine-day itinerary was a flawless introduction to all things Éire.

— Catherine Garcia, TheWeek, 29 Sep. 2026
Fonda’s flawless silver pixie changed that, revealing his rare ability to transform gray hair from some something to be concealed into something to be expertly cultivated — a technique few colorists had dared to master.

— Maggie Ryan, Flow Space, 25 Sep. 2026

Definition of flawless

Adjective

Radio signals also behave differently underwater, making reliable communication a persistent engineering challenge.

— Aamir Khollam, Interesting Engineering, 29 Sep. 2026
Our focus is on operating a safe and reliable heating system, doing critical infrastructure work cost effectively, and helping customers make ends meet through energy-efficiency programs, budget-friendly billing plans and financial assistance.

— Sara Tenenbaum, CBS News, 29 Sep. 2026

Definition of reliable

Browse Nearby Words

foolishness

foolproof

fools

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Style

“Foolproof.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/foolproof. Accessed 1 Oct. 2026.

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Synonyms of foolproof

adjective

Example Sentences

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