Implausible and Preposterous

Implausible

Implausible adjective - Too extraordinary or improbable to believe.
Usage example: the terrorist attacks generated a whole passel of implausible conspiracy theories that dishonor the memory of those who perished

Preposterous is a synonym for implausible in outlandish topic. In some cases you can use "Preposterous" instead an adjective "Implausible", when it comes to topics like unimaginable, hard to believe.

Nearby Word: implausibly

Preposterous

Preposterous adjective - Conceived or made without regard for reason or reality.
Usage example: the idea that extraterrestrials built the pyramids is preposterous

Implausible is a synonym for preposterous in outlandish topic. You can use "Implausible" instead an adjective "Preposterous", if it concerns topics such as unimaginable.
Cite this Source
Preposterous and Implausible. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/implausible/preposterous
Implausible & Preposterous. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/implausible/preposterous>.
Preposterous or Implausible. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/implausible/preposterous.
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