Main Entry: im·preg·na·ble

Pronunciation: \im-ˈpreg-nə-bəl\

Function: adjective

Etymology: Middle English imprenable, from Middle French, from in- + prenable vulnerable to capture, from prendre to take — more at prize

Date: 15th century

1 : incapable of being taken by assault : unconquerable <an impregnable fortress>
2 : unassailable; also : impenetrable <impregnable walls>

— im·preg·na·bil·i·ty \(ˌ)im-ˌpreg-nə-ˈbi-lə-tē\ noun

— im·preg·na·ble·ness \im-ˈpreg-nə-bəl-nəs\ noun

— im·preg·na·bly \-blē\ adverb