Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Willful and impregnable are semantically related. In some cases you can use "Willful" instead an adjective "Impregnable".
Willful
Willful adjective - Given to resisting authority or another's control.
Impregnable and willful are semantically related. Sometimes you can use "Impregnable" instead an adjective "Willful".
Mutual synonyms
Cite this Source
Willful and Impregnable. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/impregnable/willful
Impregnable & Willful. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/impregnable/willful>.
Willful or Impregnable. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/impregnable/willful.
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