Hellacious
Hellacious adjective - Requiring considerable physical or mental effort.
Usage example: the pioneers survived a particularly hellacious river crossing with their covered wagon barely in one piece
Tough and hellacious are semantically related. in excellent topic. In some cases you can use "Tough" instead an adjective "Hellacious".
Tough
Tough adjective - Requiring considerable physical or mental effort.
Usage example: even if you study for it, it's still a tough exam
Hellacious and tough are semantically related. You can use "Hellacious" instead an adjective "Tough".
Mutual synonyms
Cite this Source
Tough and Hellacious. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/hellacious/tough
Hellacious & Tough. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/hellacious/tough>.
Tough or Hellacious. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/hellacious/tough.
Google Ngram Viewer shows how "hellacious" and "tough" have occurred on timeline