As adjectives the difference between foolproof and failproof
is that foolproof is for a device: protected, or designed to be proof against misuse or error; fail-safe while failproof is resistant to failure; that cannot go wrong.
As a verb foolproof
is {{cx|transitive|lang=en}} To make foolproof.
foolproof
English
Adjective
(
en adjective)
For a device: protected, or designed to be proof against misuse or error; fail-safe.
For an idea or plan: infallible, or bulletproof.
failproof
English
Adjective
(
en adjective)
Resistant to failure; that cannot go wrong.
Synonyms
* failureproof