# foolproof

> English word · Adjective · IPA /ˈfuːl ˌpɹuːf/ · frequency rank #34,062

## Definitions
1. Of a device: protected against, or designed to be proof against, misuse or error.
2. Of an idea or plan: certain to succeed in all eventualities, or claimed to be so; infallible.

## Etymology
From fool + -proof.

## Common misspellings (13)
`ffoolproof`, `foloproof`, `folproof`, `foollproof`, `foolporof`, `foolpproof`, `foolprof`, `foolprofo`, `foolprooff`, `foolprroof`, `foolrpoof`, `fooplroof`, `ofolproof`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/foolproof