Challenging
Challenging adjective - Requiring much time, effort, or careful attention.
Usage example: a challenging test designed to whittle down the number of contestants
Rigid and challenging are semantically related. In some cases you can use "Rigid" instead an adjective "Challenging".
Rigid
Rigid adjective - Not allowing for any exceptions or loosening of standards.
Challenging and rigid are semantically related. Sometimes you can use "Challenging" instead an adjective "Rigid".
Mutual synonyms
Related pairs
Cite this Source
Rigid and Challenging. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/challenging/rigid
Challenging & Rigid. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/challenging/rigid>.
Rigid or Challenging. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/challenging/rigid.
Google Ngram Viewer shows how "challenging" and "rigid" have occurred on timeline