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 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 The foolproof outfit formula simplifies everyday dressing and delivers double the styling options. — Kyra Surgent, InStyle, 15 Aug. 2026 No duh — the stars happen to be adorable puppies, and the stories sound a constant theme, that good things come in small packages, a foolproof rallying cry that fills the hearts of its target audience. — Randy Myers, Mercury News, 12 Aug. 2026 That sandboxing and permission process baked into the Cloudflare OS framework could prove helpful in practice, even if no system is foolproof. — Jeremy Hsu, ArsTechnica, 6 Aug. 2026 See All Example Sentences for foolproof

Recent Examples of Synonyms for foolproof

Adjective

The pass the Netherlands forward wrapped into Alexander Isak’s feet was perfect.

— Stuart James, New York Times, 8 Sep. 2026
The Hoosiers have won 17 straight games, the longest active winning streak in the Football Bowl Subdivision, and are a perfect 16-0 at home under Cignetti.

— Arkansas Online, Arkansas Online, 8 Sep. 2026

Definition of perfect

Adjective

At the salon, the impossibly flawless-looking manager (Azmeri Haque Badhon) finds granular fault with Zai’s body, from stretchmarks to pore imperfections, signing her up to a gruelling program of treatments.

— Miriam Balanescu, IndieWire, 6 Sep. 2026
But in the playoffs, drivers didn’t have to have a flawless 10 weeks (and some races didn’t matter at all).

— Jeff Gluck, New York Times, 4 Sep. 2026

Definition of flawless

Adjective

That capability matters because HAPS platforms must maintain a tight operating area to provide reliable coverage.

— Aamir Khollam, Interesting Engineering, 3 Sep. 2026
Central to this was the control exerted in central midfield, an area patrolled by Ben Whiteman and the ever-reliable Matty James.

— Richard Sutcliffe, New York Times, 3 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 10 Sep. 2026.

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Synonyms of foolproof

adjective

Example Sentences

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