pen·​e·​trate | \ ˈpe-nə-ˌtrāt How to pronounce penetrate (audio) \
penetrated; penetrating

Definition of penetrate

transitive verb

1a : to pass into or through this route … penetrates the leading resort and lake areasAmerican Guide Series: Minnesota Only a dirt road penetrates the rough, wooded terrain.
b : to enter by overcoming resistance : pierce This bullet can penetrate armor.
c : to gain entrance to an apartment that I now penetrated for the first time— Osbert Lancaster
2a : to see into or through their keen eyes can penetrate the water to a depth of … forty feet— L. K. Porritt
b : to discover the inner contents or meaning of a scientific secret which will eventually be penetrated by other countries— Vera M. Dean
3 : to affect profoundly with feeling men may still be penetrated with awe by the divine righteousness— R. W. Dale
4 : to diffuse through or into the cold began to penetrate his bones— E. K. Gann

intransitive verb

1a : to pass, extend, pierce, or diffuse into or through something fishes … which enter tidal rivers and penetrate almost to fresh water— J. L. B. Smith
b : to pierce something with the eye or mind strained his eyes to penetrate beyond the thick cloud of dust insight that penetrates to the very heart of some … problem— W. F. Hambly
2 : to affect deeply the senses or feelings the suggestion might penetrate deeply enough … to make her a good deal more wary— H. A. Overstreet

Synonyms & Antonyms for penetrate



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Choose the Right Synonym for penetrate

enter, penetrate, pierce, probe mean to make way into something. enter is the most general of these and may imply either going in or forcing a way in. entered the city in triumph penetrate carries a strong implication of an impelling force or compelling power that achieves entrance. the enemy penetrated the fortress pierce means an entering or cutting through with a sharp pointed instrument. pierced the boil with a lancet probe implies penetration to investigate or explore something hidden from sight or knowledge. probed the depths of the sea

Examples of penetrate in a Sentence

These bullets can penetrate armor. radiation penetrating the Earth's atmosphere The bullet failed to penetrate. The heat penetrated through the wall. The roots of these plants have been known to penetrate to a depth of more than 15 feet. My car's headlights couldn't penetrate the dense fog. See More
Recent Examples on the Web That explains why there was a cloud with water droplets perhaps higher than the freezing line (since that shallow warm layer got bent upward), and why the actual cloud was thin enough that light was able to penetrate through. Matthew Cappucci, Washington Post, 9 Aug. 2022 Only a direct strike with a powerful weapon would penetrate the reactors’ yard-thick concrete containment vessels, said Dmytro Orlov, the exiled mayor of the city of Enerhodar, where the reactor is, and a former engineer at the plant. New York Times, 1 Aug. 2022 To image different body systems, Zhao’s team tested versions of the probe that produce waves at different frequencies and thus penetrate the body to different depths. Sophie Bushwick, Scientific American, 29 July 2022 The weather service expects more marine air will penetrate the Coast Range by Saturday afternoon bringing some slight cooling to the mid and southern Willamette Valley. oregonlive, 29 July 2022 And with a Summer Olympics date set for Los Angeles in 2028, how to penetrate the US market emerged as a huge concern for World Athletics president Sebastian Coe. Globe Staff,, 25 July 2022 Everybody loves the former Alabama and New York Jets quarterback who transcended football to penetrate the pop culture world with his unique crossover appeal during the 1960s and ‘70s. Ben Flanagan |, al, 22 July 2022 One factor is the difference in how fast new services penetrate the Japanese marketplace compared to other countries. Billboard Japan, Billboard, 19 July 2022 Given the endless expansion of attack surfaces and the relentless efforts of cybercriminals to penetrate networks, a new approach to prevention, forget detection, is certainly worth exploring. Dustin Webber, Forbes, 11 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'penetrate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of penetrate

circa 1530, in the meaning defined at transitive sense 1a

History and Etymology for penetrate

Latin penetratus, past participle of penetrare, from penitus deep within, far; akin to Latin penus provisions

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Time Traveler for penetrate

Time Traveler

The first known use of penetrate was circa 1530

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Dictionary Entries Near penetrate



penetrate someone's disguise

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Statistics for penetrate

Last Updated

17 Aug 2022

Cite this Entry

“Penetrate.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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More Definitions for penetrate


pen·​e·​trate | \ ˈpe-nə-ˌtrāt How to pronounce penetrate (audio) \
penetrated; penetrating

Kids Definition of penetrate

1 : to pass into or through A nail penetrated the tire. But his voice was not strong enough to penetrate the thick wall.— E. B. White, Stuart Little
2 : to see into or through My eyes couldn't penetrate the darkness.


pen·​e·​trate | \ ˈpen-ə-ˌtrāt How to pronounce penetrate (audio) \
penetrated; penetrating

Medical Definition of penetrate

transitive verb

1 : to pass into or through enzymes that help the sperm penetrate the zona pellucida— Anna Maria Gillis
2 : to insert the penis into the vagina of in copulation

intransitive verb

: to pass, extend, pierce, or diffuse into or through something penetrating percutaneous nephroscopy or ureteroscopy— R. A. Riehle et al.

More from Merriam-Webster on penetrate

Nglish: Translation of penetrate for Spanish Speakers

Britannica English: Translation of penetrate for Arabic Speakers


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