Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Known and impregnable are semantically related. In some cases you can use "Known" instead an adjective "Impregnable".
Known
Known adjective - Apprehended with certainty.
Impregnable and known are semantically related. Sometimes you can use "Impregnable" instead an adjective "Known".
Mutual synonyms
Both words in one sentence
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Also known for having endured a horrific stream of personal (and ultimately nationwide) disasters with nigh impregnable stride.
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There's Styx, an impregnable Decepticon prisoner, where the life-expectancy of its prisoners is very short, and only two known break-ins have worked.
Source: The Alcatraz - During the first campaign of the Siege of Osaka (1614-15, also known as the Toyotomi clan's last stand) Yukimura was in charge of planning the defense of Osaka castle, which he did so well that the castle was nigh impregnable.
Source: Useful Notes / Sanada Yukimura
Cite this Source
Known and Impregnable. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/impregnable/known
Impregnable & Known. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/impregnable/known>.
Known or Impregnable. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/impregnable/known.
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