impregnably

/ɪmˈprɛɡnəbli/
adverb
  1. In a way that cannot be captured, defeated, or overcome; invincibly.
    • The castle stood impregnably on the cliff, defying all attackers.
    • The company's market lead seemed impregnably secure.
    • She defended her position impregnably during the debate.
Antonyms
What does "impregnably" mean? | whatsthatwordmean | whatsthatwordmean