Impossible
Impossible adjective - Incapable of being solved or accomplished.
Inefficacious and impossible are semantically related. In some cases you can use "Inefficacious" instead an adjective "Impossible".
Nearby Words: impossibility, impossibly
Inefficacious
Inefficacious adjective - Producing no results.
Usage example: an inefficacious medication for a rare form of tuberculosis
Impossible and inefficacious are semantically related. Sometimes you can use "Impossible" instead an adjective "Inefficacious".
Mutual synonyms
Cite this Source
Inefficacious and Impossible. (2016). Retrieved 2026, August 08, from https://thesaurus.plus/related/impossible/inefficacious
Impossible & Inefficacious. N.p., 2016. Web. 08 Aug. 2026. <https://thesaurus.plus/related/impossible/inefficacious>.
Inefficacious or Impossible. 2016. Accessed August 08, 2026. https://thesaurus.plus/related/impossible/inefficacious.
Google Ngram Viewer shows how "impossible" and "inefficacious" have occurred on timeline