foolproof
/ˈfulˌpruf/
adjective
- Designed or planned so well that nothing can go wrong; impossible to fail or misuse.
- The instructions are foolproof, so even a beginner can assemble the furniture.
- She gave me a foolproof recipe for chocolate cake that always turns out perfect.
- The new security system is foolproof and has never been hacked.
Antonyms