pen·e·trate | \ˈpe-nə-ˌtrāt \
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

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Synonyms & Antonyms for penetrate


access, enter, pierce


depart, exit, leave

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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.
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Recent Examples on the Web

The result is a spectrum of light waves that can penetrate skin and different levels (unlike blue light, which only reaches one). Macaela Mackenzie, Allure, "Model Amy Pejkovic Reveals Struggle With Acne — and the Light Treatment That Cleared It Up," 20 Feb. 2018 If the common element tuckpointing — and/or waterproof membrane underneath the masonry — is insufficient or deteriorated such that water is penetrating into the building cavity, the board must repair the water infiltration as a common expense. Howard Dakoff,, "What to do if water leaks into your condo unit," 7 June 2017 Those rays mainly cause sunburn, while UVA rays penetrate more deeply into the skin. Nanette Asimov,, "With Hawaii banning harmful sunscreens, what’s a responsible tourist to do?," 7 July 2018 Marinating for hours on end does not change the very shallow depth that a marinade penetrates. Becky Krystal, sacbee, "If you’re in the mood to marinate meat, soak up these tips," 26 June 2018 Seen: Full-screen image of a man with a stick as thick as a rattlesnake penetrating his neck. Marc Peruzzi, Outside Online, "19 Lessons I Learned from Extreme Sports Pros," 25 June 2018 It's earned its name because a small amount of light penetrates the region, yet not enough for photosynthesis. David Grossman, Popular Mechanics, "NASA Is Stepping Into the Twilight Zone," 19 June 2018 One of the best such books this year is historian Timothy Snyder’s essential, penetrating look at how toxic ideas, autocratic power and fake news spread from Russia into Ukraine, Western Europe and now to the White House. Time Staff, Time, "Best Nonfiction Books of 2018 So Far," 11 June 2018 After President Barack Obama’s first trip to China in 2009, one of his national security advisers had to throw away a Blackberry device because the Chinese had penetrated it, a former administration official said. NBC News, "U.S. officials prepare to thwart Chinese spying at Singapore summit," 8 June 2018

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.

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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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Learn More about penetrate

Phrases Related to penetrate

penetrate someone's disguise

Statistics for penetrate

Last Updated

12 Oct 2018

Look-up Popularity

Time Traveler for penetrate

The first known use of penetrate was circa 1530

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More Definitions for penetrate



English Language Learners Definition of penetrate

: to go through or into something

: to see or show the way through (something)

: to succeed in becoming part of (an organization, a community, etc.)


pen·e·trate | \ˈpe-nə-ˌtrāt \
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 \
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

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Comments on penetrate

What made you want to look up penetrate? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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