adj

foolproof

FOOL-proof

Foolproof (adj) means Designed so simply or solidly that it can't go wrong, even if misused. Example: “She swore by her foolproof recipe for chocolate cake.”

adj

Designed so simply or solidly that it can't go wrong, even if misused.

"She swore by her foolproof recipe for chocolate cake."

"The new lock is meant to be foolproof against tampering."

How to use foolproof

Learner’s notes

In plain EnglishSo reliable or simple that it's very hard to get wrong.

Common pairings

a foolproof plan foolproof method

Word forms

more foolproof comparative, foolproofed past tense, foolproofs singular, most foolproof superlative

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She swore by her _____ recipe for chocolate cake.

Etymology

Built from fool + proof, meaning "proof against fools," i.e. safe even from careless use.

Rhymes for foolproof

oof roof goof poof hoof woof boof aloof proof spoof sunroof fireproof

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Frequently asked questions

What does “foolproof” mean?

The word “foolproof” means designed so simply or solidly that it can't go wrong, even if misused. In plain terms, so reliable or simple that it's very hard to get wrong.

How do you pronounce “foolproof”?

“Foolproof” is pronounced FOOL-proof (/ˈfuːl ˌpɹuːf/ in IPA).

How do you use “foolproof” in a sentence?

Here is “foolproof” used in a sentence: “She swore by her foolproof recipe for chocolate cake.”

What part of speech is “foolproof”?

“Foolproof” is an adjective.

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