penetrate

American  

[pen-i-treyt] / ˈpɛn ɪˌtreɪt /

verb (used with object)

penetrated, penetrating

1. to pierce or pass into or through.

   The bullet penetrated the wall. The fog lights penetrated the mist.

2. to enter the interior of.

   to penetrate a forest.

3. to enter and diffuse itself through; permeate.

4. to arrive at the truth or meaning of; understand; comprehend.

   to penetrate a mystery.

   Synonyms:

   discern, fathom

5. to obtain a share of (a market).

   to penetrate the Canadian coffee market.

6. to affect or impress (the mind or feelings) deeply.

   Synonyms:

   touch

7. to extend influence, usually peacefully, into the affairs of (another country).

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verb (used without object)

penetrated, penetrating

1. to enter, reach, or pass through something, as by piercing.

   We penetrated to the interior of the Kasbah.

2. to be diffused through something.

3. to understand or read the meaning of something.

4. to have a deep effect or impact on someone.

penetrate British  

/ ˈpɛnɪˌtreɪt /

verb

1. to find or force a way into or through (something); pierce; enter

2. to diffuse through (a substance); permeate

3. (tr) to see through

   their eyes could not penetrate the fog

4. (tr) (of a man) to insert the penis into the vagina of (a woman)

5. (tr) to grasp the meaning of (a principle, etc)

6. (intr) to be understood

   his face lit up as the new idea penetrated

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Related Words

See pierce.

Other Word Forms

• penetrability noun
• penetrable adjective
• penetrably adverb
• penetrative adjective
• penetrator noun
• prepenetrate verb (used with object)
• unpenetrated adjective

Etymology

Origin of penetrate

First recorded in 1520–30; from Latin penetrātus “entered the interior of,” past participle of penetrāre “to enter the interior of,” from penet-, variant stem of penitus “deep down” + -āre, infinitive verb suffix, with the vowel change and addition of -r- probably by analogy with intus “inside,” intrāre “to enter” ( see enter ( def. ))

Explanation

To penetrate is to force into or pierce through. If the fog is thick as pea soup, your flashlight won’t penetrate it. If you stubbornly ignore good advice, people might say nothing can penetrate that thick skull of yours. We get penetrate from the Latin word penetrare, which combines penes ("within") and intrare ("to enter"). Penetrate crops up most often to describe entering or permeating. Blaring music penetrated every corner of the dorm and we wondered how anyone could study with that racket. Penetrate can also mean to decipher or understand: "Careful study allowed us to penetrate the mysteries of Pig Latin." Finally — no surprise, given its Latin roots — the word can be used to describe sexual intercourse.

Example Sentences

Most British spiders couldn't bite you if they tried; their fangs are too small or weak to penetrate human skin.

From BBC • Apr. 13, 2026

Investors seem increasingly spooked by Mythos, a forthcoming Anthropic model that the company has said is so powerful it could penetrate existing cyber defenses if it’s misused by bad actors.

From The Wall Street Journal • Apr. 10, 2026

Like De Zerbi, Postecoglou opted for a risky short-passing game that looked to penetrate teams through central play.

From BBC • Apr. 9, 2026

That has allowed the U.S. to establish “localized air superiority across the southern flank of the Iranian coast and penetrate their defenses with overwhelming precision and firepower,” Caine said.

From Los Angeles Times • Mar. 4, 2026

He loped steadily along, and the swarms of midges and stinging insects could not penetrate his matted hair.

From "The Book of Three" by Lloyd Alexander

Related Words

• crack
• drill
• enter
• go through
• infiltrate
• invade
• pass through
• permeate
• pervade
• puncture
• seep