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 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

This patch of land to the west of San Sebastián feels like the most perfect place on the planet, while still being a 10-minute car ride from the center of the city.

— Condé Nast, Condé Nast Traveler, 4 Aug. 2026
Incorporating them into your wardrobe couldn’t be more seamless thanks to breezy yet posh linen and cotton-blend options that are perfect for the summer’s remaining heatwaves.

— Kaitlin Clapinski, InStyle, 4 Aug. 2026

Definition of perfect

Adjective

Comedy Central became one of TV’s most reliable stand-up farm systems beginning in the 1990s, implementing a mix of showcases, half-hours, roasts, late-night blocks and festival tie-ins to elevate the medium.

— Matt Grobar, Deadline, 30 July 2026
After hiring a small 50-person crew as a test run, the railroad company found Chinese laborers to be reliable and efficient.

— Sacbee.com, Sacbee.com, 30 July 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 5 Aug. 2026.

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Synonyms of foolproof

adjective

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