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

A “foolproof” way to make the diagnosis would be news indeed!

From The Daily Beast

Geo-location services of this sort do not have absolutely foolproof accuracy.

From The Daily Beast

Cry No More Every parent tires of hearing their child cry, but not everyone finds such a foolproof way to make it stop.

From The Daily Beast

Of all the potential holiday gifts, few are as foolproof as cash or gift cards.

From The Daily Beast

Dan Gross on why the episode is a reminder that the vaunted cloud is much like the Web in the 1990s—young and far from foolproof.

From The Daily Beast

It was a nearly foolproof way to make sure that you could talk to the people you trusted, but that no one else could listen in.

From Project Gutenberg

Five hours to devise one more completely foolproof method of bringing about the eventual ruin of the association.

From Project Gutenberg

He tried to figure out some foolproof way of cabling to Havana, but the censorship hazards were too great.

From Project Gutenberg

There are a few sequences of words that really are foolproof, carrying their own atmosphere and dignity with them.

From Project Gutenberg

With the finest pen he traced the curlicues an engraving lathe had evolved to make the passes foolproof.

From Project Gutenberg

Related Words

• flawless
• reliable
• surefire
• unassailable