impenetrable

adjective

im·pen·e·tra·ble | \ (ˌ)im-ˈpe-nə-trə-bəl

Definition of impenetrable

1a : incapable of being penetrated or pierced

b : inaccessible to knowledge, reason, or sympathy : impervious

2 : incapable of being comprehended : inscrutable

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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

This was the law enforcement equivalent of some uncharted borderland, one that would prove maddeningly impenetrable to a civilian like Hampton. — Alexander Nazaryan, Newsweek, "Lie and Deny: Secrecy and Suspicion Surround the Los Angeles County Sheriff’s Department," 21 Apr. 2016 They’re seen instead as impenetrable black boxes where our most intimate personal secrets are bought and sold to further fatten a shadowy Über-class of obscene wealth and privilege trading behind velvet ropes in elite cryptocurrencies. — Jon Talton, The Seattle Times, "Another bite of the Apple: Beyond that trillion-dollar valuation," 7 Aug. 2018 This is the only team on this list to not win its bowl game, but Alabama had been impenetrable prior to its final two games of 2013. — Will Mccollister, SI.com, "On the Outside Looking In: The Best Teams to Finish No. 3 in the BCS Era," 11 July 2018 End-to-end encryption means that the message is impenetrable to everyone — including the app vendor and the network provider — except the message sender and receiver. — Barbara Krasnoff, The Verge, "What is RCS and why you might want it," 12 Dec. 2018 Drones are amazing and cool and powerful, but traditionally they can be thwarted by an impenetrable obstacle that has vexed drone creators and pilots for years: doors. — David Grossman, Popular Mechanics, "Inspired by Wasps, This Micro-Drone Lifts 40 Times its Weight," 25 Oct. 2018 In the end, there was nothing del Potro could do to break down Djokovic, the most impenetrable man in tennis. — Tom Perrotta, WSJ, "Novak Djokovic Wins the U.S. Open," 9 Sep. 2018 Despite the seemingly impenetrable wall put up around Lovato, the substances — and the seedy people — sneaked in. — Fox News, "Demi Lovato reportedly surrounded herself with enablers prior to overdose," 5 Aug. 2018 Pondering the impenetrable fog of the early universe. — Lacy Schley, Discover Magazine, "Staring Into the Abyss," 24 Nov. 2018

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