Formidable and Strenuous

Formidable

Formidable adjective - Requiring considerable physical or mental effort.
Usage example: running a marathon is a formidable undertaking

Strenuous is a synonym for formidable in difficult topic. In some cases you can use "Strenuous" instead an adjective "Formidable", when it comes to topics like onerous, arduous.

Nearby Word: formidably

Strenuous

Strenuous adjective - Requiring considerable physical or mental effort.
Usage example: a strenuous workout on the obstacle course

Formidable is a synonym for strenuous in arduous topic. You can use "Formidable" instead an adjective "Strenuous", if it concerns topics such as difficult.

Nearby Word: strenuously
Cite this Source
Strenuous and Formidable. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/formidable/strenuous
Formidable & Strenuous. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/formidable/strenuous>.
Strenuous or Formidable. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/formidable/strenuous.
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