impenetrable

adjective

im·​pen·​e·​tra·​ble (ˌ)im-ˈpe-nə-trə-bəl How to pronounce impenetrable (audio)
1
a
: incapable of being penetrated or pierced
b
: inaccessible to knowledge, reason, or sympathy : impervious
2
: incapable of being comprehended : inscrutable
impenetrably adverb

Examples of impenetrable in a Sentence

The fort's defenses were thought to be impenetrable. the ancient temple was surrounded by vast stretches of impenetrable jungle
Recent Examples on the Web Both Hezbollah and the Houthis have deployed precision missiles and drones in their attacks, and although Israel has impressive defense capabilities against ballistic missiles, cruise missiles, and drones, its defenses are not impenetrable. Amos Yadlin, Foreign Affairs, 8 Mar. 2024 His graying, thinning hair, tense figure and pouchy eyes could pierce Larry’s otherwise impenetrable ego. Boris Kachka, Washington Post, 29 Feb. 2024 To make matters worse, amidst the nearly impenetrable matrix of vegetation swallowing up headstones, Palmer and a group of Boy Scouts that had come to clear the land encountered a group of deer hunters. USA TODAY, 14 Feb. 2024 In California this year, the news was often dominated by jaw-dropping weather — roiling floodwaters, impenetrable snow, even a hurricane. Times Photography Staff, Los Angeles Times, 28 Dec. 2023 Stapleton, the villain, wanders through a woolly, impenetrable fog, is sucked into a bog in the moor, and asphyxiates to death. Siddhartha Mukherjee, The New Yorker, 11 Dec. 2023 As evening shrouded the settlement in impenetrable black, Father Moisés lowered his husky frame into a hammock. Bishop Sand, Washington Post, 17 Feb. 2024 Despite the volatility, the global competition for growth is not an impenetrable mystery but an ongoing evolution that requires constant judgment. Philipp Carlsson-Szlezak, Fortune, 12 Feb. 2024 There have even been instances where a certain lineup combination played impenetrable defense, collectively earning the Lockdown Chain. Sam Cohn, Baltimore Sun, 9 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'impenetrable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Middle English impenetrabel, from Middle French impenetrable, from Latin impenetrabilis, from in- + penetrabilis penetrable

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of impenetrable was in the 15th century

Dictionary Entries Near impenetrable

Cite this Entry

“Impenetrable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impenetrable. Accessed 19 Mar. 2024.

Kids Definition

impenetrable

adjective
im·​pen·​e·​tra·​ble (ˈ)im-ˈpen-ə-trə-bəl How to pronounce impenetrable (audio)
1
: impossible to get through or into
impenetrable walls
impenetrable jungle
2
: impossible to understand
an impenetrable mystery
impenetrability
(ˌ)im-ˌpen-ə-trə-ˈbil-ət-ē
noun
impenetrably adverb

More from Merriam-Webster on impenetrable

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