Fool
Fool adjective - Showing or marked by a lack of good sense or judgment.
Usage example: he's always got some fool plan or other
Unreasonable and fool are semantically related. In some cases you can use "Unreasonable" instead an adjective "Fool".
Unreasonable
Unreasonable adjective - Having no basis in reason or fact.
Fool and unreasonable are semantically related. Sometimes you can use "Fool" instead an adjective "Unreasonable".
Cite this Source
Unreasonable and Fool. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/fool/unreasonable
Fool & Unreasonable. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/fool/unreasonable>.
Unreasonable or Fool. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/fool/unreasonable.
Google Ngram Viewer shows how "fool" and "unreasonable" have occurred on timeline