Certain
Foolproof
Foolproof adjective - Not liable to failure.
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Synonyms for Foolproof
Certain is a synonym for foolproof in infallible topic. You can use "Certain" instead an adjective "Foolproof".
Mutual synonyms
Both words in one sentence
- They do lampshade this by claiming it's definitely not a foolproof method, and they only seem to believe it for certain if you have at least three of the same Pokémon (though one or two still puts you on their radar), but still.
Source: Fanfic / Pedestal - There's slightly more to it in that the viewscreen on the environment suits fools the condemned into seeing a certain something that isn't actually there, which acts as subtle but nigh foolproof psychological incentive to clean the Silo's cameras.
Source: Literature / Wool
Cite this Source
Foolproof and Certain. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/certain/foolproof
Certain & Foolproof. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/certain/foolproof>.
Foolproof or Certain. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/certain/foolproof.
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