impénétrable

impenetrable, impervious

adjective ahm-peh-neh-TRAH-bluh Rare

Origin: Latin impenetrabilis

Also means

inscrutable (of a person)

Usage Note

Impénétrable describes both physical barriers (a forest so dense it cannot be entered) and psychological opacity (an expression that reveals nothing): un visage impénétrable ('an inscrutable face'). Its positive counterpart pénétrable exists but is rare. The adverb impénétrablement is found mostly in literary prose.

Examples

"La forêt était dense et impénétrable."

Natural Translation

The forest was dense and impenetrable.

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