adj, verb ·Moderate ·College level

Definitions

Verb

1. 1
   To render (something) foolproof. transitive

   "We foolproofed the operations."

2. 2
   proof against human misuse or error wordnet

Adjective

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

Adjective

1. 1
   not liable to failure wordnet

Synonyms

All synonyms

infallibleadaptableairtightballproofbombproofbulletproof

Example

More examples

"No security system is foolproof."

Etymology

From fool + -proof.

Related phrases

idiot proof

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.