Bad
Bad adjective - Falling short of a standard.
Impregnable and bad are semantically related. In some cases you can use "Impregnable" instead an adjective "Bad".
Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Bad and impregnable are semantically related. Sometimes you can use "Bad" instead an adjective "Impregnable".
Mutual synonyms
Both words in one sentence
- Cardboard Prison / The Alcatraz: The facility for imprisoning captured supervillains, nicknamed Superjail, is an impregnable high-tech fortress... which bad guys still regularly worm their way out of.
Source: Roleplay / Cape and Cowl
Cite this Source
Impregnable and Bad. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/bad/impregnable
Bad & Impregnable. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/bad/impregnable>.
Impregnable or Bad. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/bad/impregnable.
Google Ngram Viewer shows how "bad" and "impregnable" have occurred on timeline