Impenetrable
Impenetrable adjective - Impossible to get through or into.
Secure and impenetrable are semantically related. in property topic. In some cases you can use "Secure" instead an adjective "Impenetrable".
Nearby Words: impenetrability, impenetrably
Secure
Secure adjective - Having or showing great faith in oneself or one's abilities.
Impenetrable and secure are semantically related. Sometimes you can use "Impenetrable" instead an adjective "Secure".
Mutual synonyms
Cite this Source
Secure and Impenetrable. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/impenetrable/secure
Impenetrable & Secure. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/impenetrable/secure>.
Secure or Impenetrable. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/impenetrable/secure.
Google Ngram Viewer shows how "impenetrable" and "secure" have occurred on timeline