Definition of foolproof
- a foolproof plan
DNA fingerprinting gives police a virtually foolproof way to link a suspect to a crime scene.
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.
: done, made, or planned so well that nothing can go wrong
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