n. [ Cf. F. impénétrabilité. ]
a. [ L. impenetrabilis; pref. im- not + penetrabilis penetrable: cf. F. impénétrable. ]
Highest woods impenetrable
To star or sunlight. Milton. [ 1913 Webster ]
They will be credulous in all affairs of life, but impenetrable by a sermon of the gospel. Jer. Taylor. [ 1913 Webster ]
n. The quality of being impenetrable; impenetrability. [ 1913 Webster ]
adv. In an impenetrable manner or state; imperviously. “Impenetrably armed.” Milton. “Impenetrably dull.” Pope. [ 1913 Webster ]