Impenetrable - definition, pronunciation, transcription
The fort's defenses were thought to be impenetrable.
...the ancient temple was surrounded by vast stretches of impenetrable jungle...
His theory was absolutely impenetrable.
The trees formed a dark and impenetrable barrier.
the impenetrable blackness of the night
...an impenetrable fog overcast our view of the harbor...
...during the cold war East and West Berlin were sundered by an impenetrable wall...