Where Does Foolproof Come from?

The term "foolproof" originates in 1902. The term "idiot-proof" became popular in the 1970s. It may have been invented as a stronger-sounding version of foolproof, as the force of foolproof had declined due to frequent usage.

Is it fail proof or foolproof?

Is it fullproof or foolproof? Foolproof is an adjective that means impervious to damage at the hands of fools. Fullproof is a spelling mistake based on the similar pronunciations of the words fool and full.

Whats foolproof means?

: so simple, plain, or reliable as to leave no opportunity for error, misuse, or failure a foolproof plan.