foolproof

[fool-proof] / ˈfulˌpruf /

ADJECTIVE

infallible

Synonyms

STRONGEST

flawless reliable surefire unassailable

STRONG

goofproof guaranteed perfect tested tried

WEAK

certain dependable fail-safe faultless idiot-proof never-failing safe sure unerring unfailing

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Now Huffington jokes that she has a foolproof plan to ensure that the Knicks will clinch their first championship in 53 years on Saturday night in San Antonio.

From The Wall Street Journal • Jun. 11, 2026

But the Dutch blueprint isn't foolproof - youth unemployment is rising.

From BBC • Jun. 7, 2026

While some might think signing Bauer might be a risky move for an MLB organization, Bauer feels his plan is foolproof in that regard.

From Los Angeles Times • May 8, 2026

Kelly is no foolproof indicator of where the right is headed; she bet against Trump, after all.

From Slate • May 6, 2026

I guess the main reason I felt this way was because Papa and I had figured out a quick and nearly foolproof way of doing it.

From "Old Yeller" by Fred Gipson

Vocabulary lists containing foolproof

Game Changer

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Old Yeller

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The Bad Beginning

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