Synonyms of foolproof

Verb

1. goofproof, goof-proof, foolproof, proof

usage: proof against human misuse or error; "foolproof this appliance"

Adjective

1. foolproof, unfailing, infallible (vs. fallible)

usage: not liable to failure; "a foolproof identification system"; "the unfailing sign of an amateur"; "an unfailing test"

Definition and meaning of foolproof (Dictionary)