foolproof

[ fool-proof ]

adjective

1. involving no risk or harm, even when tampered with.
2. never-failing:

   a foolproof method.

foolproof

/ ˈfuːlˌpruːf /

adjective

1. proof against failure; infallible

   a foolproof idea

2. (esp of machines) proof against human misuse, error, etc

Word History and Origins

Origin of foolproof¹

An Americanism dating back to 1900–05; fool ¹ + -proof

Example Sentences

It’s always a good idea to wash produce for that reason, but it’s not foolproof.

From Slate

It is remarkably uncomplicated and virtually foolproof.

From Salon

While 2FA enhances security, it can also foster a false sense of confidence. 2FA seems foolproof, leading many people to pay less attention to other security practices, like using strong, unique passwords for each account.

From Salon

"That was clearly a foolproof plan given I'm reading those texts to you right now," Oliver joked.

From Salon

Also, safeguarding checks are not foolproof because they don't necessarily mean that suspects can't move into other organisations and perpetrate abuse.

From BBC

Related Words

• flawless
• reliable
• surefire
• unassailable