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Showing results for impenetrable. Search instead for impenetrab.
Definitions

impenetrable

[im-pen-i-truh-buhl] / ɪmˈpɛn ɪ trə bəl /
ADJECTIVE
dense
Synonyms
STRONGEST
bulletproof impassable impervious
WEAK
close compact firm hard hermetic impermeable inviolable solid substantial thick unpiercable
Antonyms
STRONGEST
open
WEAK
clear comprehensible intelligible penetrable permeable porous soft thin understandable
ADJECTIVE
incomprehensible
Synonyms
STRONGEST
arcane baffling inexplicable inscrutable mysterious unaccountable unfathomable unintelligible
WEAK
Delphic cabalistic dark enigmatic enigmatical hidden incognizable indiscernible mystic obscure sibylline ungraspable unknowable
Antonyms
STRONGEST
clear comprehensible explainable explicable intelligible known obvious plain
WEAK
penetrable permeable porous soft thin understandable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Bent on surviving the trip, she decides early to bury her feelings in an impenetrable “garb of stone” and to fashion for herself an imperious personality.

From The Wall Street Journal • Apr. 3, 2026

Unai Emery's side are being questioned after winning two of their past six Premier League games, and falling to three home defeats in five matches at the once impenetrable Villa Park.

From BBC • Feb. 26, 2026

The primary difference between public and private prisons, experts told Salon, is that private prisons operate in an even more impenetrable black box than public prisons.

From Salon • Jan. 28, 2026

A poorly cleared corner followed by an unfortunate deflection proved fatal to the hitherto impenetrable Parisian defence.

From Barron's • Jan. 20, 2026

Then again, I'd thought the metal door was impenetrable....

From "City of the Plague God" by Sarwat Chadda