Fallacious and Perfidious

Fallacious

Fallacious adjective - Tending or having power to deceive.
Usage example: consumers who harbor the fallacious belief that credit-card spending will never catch up with them

Perfidious and fallacious are semantically related. In some cases you can use "Perfidious" instead an adjective "Fallacious".

Perfidious

Perfidious adjective - Not true in one's allegiance to someone or something.

Fallacious and perfidious are semantically related. Sometimes you can use "Fallacious" instead an adjective "Perfidious".

Nearby Words: perfidy, perfidiously
Cite this Source
Perfidious and Fallacious. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/fallacious/perfidious
Fallacious & Perfidious. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/fallacious/perfidious>.
Perfidious or Fallacious. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/fallacious/perfidious.
Google Ngram Viewer shows how "fallacious" and "perfidious" have occurred on timeline