verb pen·e·trate \ ˈpe-nə-ˌtrāt \
|Updated on: 8 Jun 2018

Definition of penetrate

penetrated; penetrating
1 a : to pass into or through
  • this route … penetrates the leading resort and lake areas
  • American 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
2 a : 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
1 a : 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

Examples of penetrate in a Sentence

  1. These bullets can penetrate armor.

  2. radiation penetrating the Earth's atmosphere

  3. The bullet failed to penetrate.

  4. The heat penetrated through the wall.

  5. The roots of these plants have been known to penetrate to a depth of more than 15 feet.

  6. My car's headlights couldn't penetrate the dense fog.

Recent Examples of penetrate from the Web

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.

Origin and Etymology of penetrate

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

penetrate Synonyms

Synonym Discussion of 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

PENETRATE Defined for English Language Learners


Definition of penetrate for English Language Learners

  • : 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.)

PENETRATE Defined for Kids


verb pen·e·trate \ ˈpe-nə-ˌtrāt \

Definition of penetrate for Students

penetrated; penetrating
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.

Medical Dictionary


verb pen·e·trate \ ˈpen-ə-ˌtrāt \

medical Definition of penetrate

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

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the quality or state of being insatiable

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