Rigorous
Uphill
Uphill adjective - Requiring considerable physical or mental effort.
Usage example: an uphill battle to eradicate poverty in an area of the state that has never known anything else
Mutual synonyms
Cite this Source
Uphill and Rigorous. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/rigorous/uphill
Rigorous & Uphill. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/rigorous/uphill>.
Uphill or Rigorous. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/rigorous/uphill.
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