Fallacious
Fallacious adjective - Not using or following good reasoning.
Usage example: it's fallacious to say that something must exist because science hasn't proven its nonexistence
Insane and fallacious are semantically related. In some cases you can use "Insane" instead an adjective "Fallacious".
Insane
Insane adjective - Showing or marked by a lack of good sense or judgment.
Usage example: an insane plan to blow all of their savings on lottery tickets
Fallacious and insane are semantically related. Sometimes you can use "Fallacious" instead an adjective "Insane".
Mutual synonyms
Cite this Source
Insane and Fallacious. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/fallacious/insane
Fallacious & Insane. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/fallacious/insane>.
Insane or Fallacious. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/fallacious/insane.
Google Ngram Viewer shows how "fallacious" and "insane" have occurred on timeline