penetrate

UK: /ˈpɛnətreɪt/ US: /ˈpɛnɪˌtreɪt/ ,(pen′i trāt′)

Inflections of 'penetrate' (v): (⇒ conjugate)

penetrates

v 3rd person singular

penetrating

v pres p

penetrated

v past

penetrated

v past p

WordReference Random House Learner's Dictionary of American English © 2025

pen•e•trate /ˈpɛnɪˌtreɪt/   v., -trat•ed, -trat•ing. 

1. to pierce or pass into or through: [~ + object]
   The bullet penetrated the wall.
   [no object]
   Maybe the bullet didn't penetrate.
2. to enter the interior of: [~ + object]
   to penetrate a forest.
   [no object]
   The explorers penetrated into the interior.
3. to spread through; seem to be everywhere in;
   permeate: [~ + object]
   The tobacco smoke penetrated the room.
   [no object]
   That cigarette smoke really penetrates, doesn't it?
4. to arrive at the meaning of;
   comprehend:
   [~ + object] to penetrate the mysteries of Einstein's theories.
5. to obtain a share of (a market):
   [~ + object] to penetrate the coffee market.

pen•e•tra•ble /ˈpɛnɪtrəbəl/  adj. 

WordReference Random House Unabridged Dictionary of American English © 2025

pen•e•trate  (pen′i trāt′), v., -trat•ed, -trat•ing. 
v.t. 

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.
5. to obtain a share of (a market):
   to penetrate the Canadian coffee market.
6. to affect or impress (the mind or feelings) deeply.
7. to extend influence, usually peacefully, into the affairs of (another country).

v.i. 

8. to enter, reach, or pass through something, as by piercing:
   We penetrated to the interior of the Kasbah.
9. to be diffused through something.
10. to understand or read the meaning of something.
11. to have a deep effect or impact on someone.

• Latin penetrātus (past participle of penetrāre), equivalent. to penet-, variant stem of penitus deep down + -r- (probably by analogy with intus inside:
  intrāre
  to enter) + -ātus + -ate¹
• 1520–30

pen′e•tra′tor, n. 
Synonyms

• 1. See pierce. 
• 4. fathom, discern.
• 6. touch.

Collins Concise English Dictionary © HarperCollins Publishers::

penetrate / ˈpɛnɪˌtreɪt/ verb

1. to find or force a way into or through (something); pierce; enter
2. to diffuse through (a substance); permeate
3. (transitive) to see through: their eyes could not penetrate the fog
4. (transitive) (of a man) to insert the penis into the vagina or anus of (a person)
5. (transitive) to grasp the meaning of (a principle, etc)
6. (intransitive) to be understood: his face lit up as the new idea penetrated

Etymology: 16th Century: from Latin penetrāre; related to penitus inner, and penus the interior of a house

ˌpenetraˈbility, ˈpenetrableness / ˈpɛnɪtrəb^əlnəs/ noun

ˈpeneˌtrator noun