Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Viable and impregnable are semantically related. In some cases you can use "Viable" instead an adjective "Impregnable".
Viable
Viable adjective - Capable of being done or carried out.
Impregnable and viable are semantically related. Sometimes you can use "Impregnable" instead an adjective "Viable".
Nearby Word: viability
Mutual synonyms
Cite this Source
Viable and Impregnable. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/impregnable/viable
Impregnable & Viable. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/impregnable/viable>.
Viable or Impregnable. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/impregnable/viable.
Google Ngram Viewer shows how "impregnable" and "viable" have occurred on timeline