Formidable and Impregnable

Formidable

Formidable adjective - Causing fear.

Impregnable and formidable are semantically related in dreadful topic. In some cases you can use "Impregnable" instead an adjective "Formidable", when it comes to topics like horrible.

Nearby Word: formidably

Impregnable

Impregnable adjective - Incapable of being defeated, overcome, or subdued.

Formidable and impregnable are semantically related in dreadful topic. Sometimes you can use "Formidable" instead an adjective "Impregnable".

Cite this Source
Impregnable and Formidable. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/formidable/impregnable
Formidable & Impregnable. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/formidable/impregnable>.
Impregnable or Formidable. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/formidable/impregnable.
Google Ngram Viewer shows how "formidable" and "impregnable" have occurred on timeline