fool·​proof | \ ˈfül-ˌprüf \

Definition of foolproof

: so simple, plain, or reliable as to leave no opportunity for error, misuse, or failure a foolproof plan

Examples of foolproof in a Sentence

DNA fingerprinting gives police a virtually foolproof way to link a suspect to a crime scene.

Recent Examples on the Web

Which made fish the perfect meat with which to experiment on this supposedly foolproof machine. James Lynch, Popular Mechanics, "Late to the Party: Sous Vide," 12 Dec. 2018 Get a foolproof system to pay the rest of your bills — on time. Rhonda Abrams, USA TODAY, "8 not-so-sexy tasks for entrepreneurs," 31 Jan. 2018 Photographed for Woman's Day by Sam Gray Basket Case Using matching labels is a great way to unify baskets of different shapes and sizes, and create a foolproof organizing system. Staff, Woman's Day, "7 New Ways to Decorate With Wallpaper," 26 Mar. 2010 Check out Curbed’s holiday gift guide and foolproof book roundup. Jenny Xie, Curbed, "Best Cyber Monday deals on furniture, bedding, and more," 24 Nov. 2018 Not everything will be foolproof — but that’s what makes life fun. Aliza Kelly Faragher, Allure, "The Basics of Numerology: How to Calculate Your Life Path and Destiny Numbers," 16 July 2018 Electronic voting machines can be hacked, and there's no foolproof way to prevent or even detect attacks on voting machines. Timothy B. Lee, Ars Technica, "Experts criticize West Virginia’s plan for smartphone voting," 7 Aug. 2018 The hardy exterior base allows for a candle pot to be moved around the house easily while the diverse range of colors, sizes, and scents enable foolproof integration into any space. Kaitlin Clark, Curbed, "A beginner’s guide to decorating with candles," 23 July 2018 Money is not necessarily a foolproof measure of campaign strength by any means. Adrian Walker,, "The Democrats running for governor must be wondering when the cavalry arrives," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'foolproof.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of foolproof

1902, in the meaning defined above

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Statistics for foolproof

Last Updated

6 Jan 2019

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Time Traveler for foolproof

The first known use of foolproof was in 1902

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More Definitions for foolproof



English Language Learners Definition of foolproof

: done, made, or planned so well that nothing can go wrong


fool·​proof | \ ˈfül-ˈprüf \

Kids Definition of foolproof

: done, made, or planned so well that nothing can go wrong a foolproof recipe

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More from Merriam-Webster on foolproof

Rhyming Dictionary: Words that rhyme with foolproof

Thesaurus: All synonyms and antonyms for foolproof

Spanish Central: Translation of foolproof

Nglish: Translation of foolproof for Spanish Speakers

Comments on foolproof

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marked by shyness and lack of polish

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