fool·​proof | \ ˈfül-ˌprüf How to pronounce foolproof (audio) \

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

Nuclear waste is currently stored in cooling pools at reactor sites, but these are not foolproof, says Greenpeace. Julie Zaugg And Nanlin Fang, CNN, "China plans giant underground lab to research nuclear waste," 6 Sep. 2019 At its core, free money is quite simply a foolproof bet. Jim Ayello, Indianapolis Star, "Insider: Sports gambling is legal in Indiana! Let's bet on the Colts," 4 Sep. 2019 The indictment notes the scheme was not foolproof, with the traders sometimes not cancelling the orders fast enough. NBC News, "Justice Department charges three traders in market manipulation scheme," 16 Sep. 2019 This is a foolproof way to torch calories while staying cool. Stephanie Mansour, NBC News, "5 tips for exercising outdoors in warm weather," 9 Sep. 2019 How to avoid getting conned online There is no foolproof way to prevent yourself from getting taken advantage of in an online transaction, but there are ways to minimize the chances, said Tempe police Detective Greg Bacon, a department spokesman. Paulina Pineda, azcentral, "This man posted a room for rent in a home he didn't own, police say," 22 Aug. 2019 The screening process, however, is not foolproof: The assessments are often held in spaces that are loud and lack privacy, which prevents individuals from being fully open about their conditions, Tartaro said. Catherine Kim, Vox, "Jeffrey Epstein’s death and America’s jail suicide problem," 14 Aug. 2019 Plus, food is often seen as a foolproof way of bringing people together. Michelle Cheng, Quartz at Work, "The arrival of a pizza-party planning service for remote workers is a sign of the times," 26 July 2019 But that's not foolproof, so Rooney told CBS News that some companies employ other shadowy tactics. Jim Axelrod, CBS News, "CBS News investigation finds fraudulent court orders used to change Google search results," 25 July 2019

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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Last Updated

13 Oct 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 How to pronounce foolproof (audio) \

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

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