Challenging
Challenging adjective - Requiring considerable physical or mental effort.
Usage example: an exceptionally challenging brainteaser
Formidable is a synonym for challenging in difficult topic. In some cases you can use "Formidable" instead an adjective "Challenging", when it comes to topics like ambitious.
Formidable
Formidable adjective - Requiring considerable physical or mental effort.
Usage example: running a marathon is a formidable undertaking
Challenging is a synonym for formidable in difficult topic. You can use "Challenging" instead an adjective "Formidable", if it concerns topics such as demanding, ambitious.
Nearby Word: formidably
Mutual synonyms
Related pairs
- strenuous and challenging
- strenuous and formidable
- stiff and challenging
- stiff and formidable
- demanding and challenging
- demanding and formidable
- difficult and challenging
- difficult and formidable
- heavy and challenging
- heavy and formidable
- ambitious and challenging
- ambitious and formidable
- hard and challenging
- hard and formidable
Cite this Source
Formidable and Challenging. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/challenging/formidable
Challenging & Formidable. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/challenging/formidable>.
Formidable or Challenging. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/challenging/formidable.
Google Ngram Viewer shows how "challenging" and "formidable" have occurred on timeline