The fort's defenses were thought to be impenetrable.
the ancient temple was surrounded by vast stretches of impenetrable jungle
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'impenetrable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 15th century
in the meaning defined at sense 1a
See Words from the same yearincomprehensible, unfathomable, ungraspable, unintelligible;
basic, elemental, elementary, essential, fundamental, rudimentary, underlying;
coherent, connected, ordered, orderly, organized, systematic, systematized;
clear, cogent, compelling, convincing, lucid, pellucid, perspicuous, plain, straightforward;
abstruse, enigmatic (also enigmatical), esoteric, indecipherable, inscrutable, recondite, unsearchable;
cryptic, darkling, deep, mysterious, mystic, oblique, obscure, occult, uncanny;
baffling, bewildering, confounding, confusing, mystifying, perplexing, puzzling;
: impossible to pass or see through
: impossible to understand
Thesaurus: All synonyms and antonyms for impenetrable Spanish Central: Translation of impenetrable Nglish: Translation of impenetrable for Spanish speakers Britannica English: Translation of impenetrable for Arabic speakers
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