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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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 Briceno says gel pencils are also a foolproof way to introduce color. — Marci Robin, Allure, 24 July 2026 So mathematicians try to come up with foolproof methods for differentiating them. — Joseph Howlett, Scientific American, 23 July 2026 Read on for five foolproof ideas for what shoes to wear with satin pants, all inspired by street-style looks and ready to upgrade your early-fall rotation. — India Roby, Glamour, 16 July 2026 Fortunately, Jennifer Garner lent us a foolproof formula while on a recent trip with her family in Virginia. — Better Homes & Gardens, 16 July 2026 See All Example Sentences for foolproof

Recent Examples of Synonyms for foolproof

Adjective

Although umbrella insurance is far from perfect ― for instance, intentional acts are generally excluded ― umbrella insurance can provide much larger coverage amounts for things already covered by other policies with lower limits.

— Jay Adkisson, Forbes.com, 11 Aug. 2026
Brionna Jones, returning from injury and still finding her footing, went a perfect 5-of-5 from the field for 15 points.

— Christopher Harris, CBS News, 11 Aug. 2026

Definition of perfect

Adjective

Most glaring is the disparity between the top-tier clinical protocols and the logistics, which are more hapless than flawless.

— Mark Ellwood, Robb Report, 8 Aug. 2026
Their skin is flawless, their cheeks rosy, their bodies unmarked by the forces of gravity or physical strain.

— Carmen Rosenberg-Miller, Artforum, 6 Aug. 2026

Definition of flawless

Adjective

Demand planning capabilities on the Blue Yonder Platform utilize patented algorithms and advanced machine learning models to ensure that demand forecasting is not only highly accurate, but reliable.

— Arthur Zaczkiewicz, Footwear News, 13 Aug. 2026
Later reports would place the bear’s weight as high as 600 pounds, but the most reliable estimates were less than 250.

— Paul Schullery, Outdoor Life, 13 Aug. 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 17 Aug. 2026.

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Synonyms of foolproof

adjective

Example Sentences

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Cite this Entry

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