Impregnable
Impregnable adjective - Incapable of being defeated, overcome, or subdued.
Labored and impregnable are semantically related. In some cases you can use "Labored" instead an adjective "Impregnable".
Labored
Labored adjective - Requiring or showing effort.
Impregnable and labored are semantically related. Sometimes you can use "Impregnable" instead an adjective "Labored".
Mutual synonyms
Cite this Source
Labored and Impregnable. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/impregnable/labored
Impregnable & Labored. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/impregnable/labored>.
Labored or Impregnable. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/impregnable/labored.
Google Ngram Viewer shows how "impregnable" and "labored" have occurred on timeline