Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Valid and impregnable are semantically related. In some cases you can use "Valid" instead an adjective "Impregnable".
Valid
Valid adjective - According to the rules of logic.
Impregnable and valid are semantically related. Sometimes you can use "Impregnable" instead an adjective "Valid".
Nearby Words: validity, validation
Mutual synonyms
Cite this Source
Valid and Impregnable. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/impregnable/valid
Impregnable & Valid. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/impregnable/valid>.
Valid or Impregnable. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/impregnable/valid.
Google Ngram Viewer shows how "impregnable" and "valid" have occurred on timeline