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.

Definitions of penetrate
  1. verb
    pass into or through, often by overcoming resistance
    synonyms: perforate
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    dig into, poke into, probe
    examine physically with or as if with a probe
    penetrate injuriously
    interpenetrate, permeate
    penetrate mutually or be interlocked
    pierce with force
    pierce or penetrate
    briefly enter enemy territory
    poke into
    enter briefly
    creep in, sneak in
    enter surreptitiously
    diffuse, imbue, interpenetrate, permeate, pervade, riddle
    spread or diffuse through
    penetrate thoroughly and into every part
    make a hole into
    pierce, thrust
    penetrate or cut through with a sharp instrument
    cut or make a way through
    force a way through
    filter, percolate, permeate, sink in
    pass through
    grain, ingrain
    thoroughly work in
    immerse, plunge
    thrust or throw into
    force, storm
    take by force
    ooze through
    run slowly and gradually
    penetrate or assault, in a harmful or injurious way
    spiritise, spiritize
    imbue with a spirit
    make a hole by poking
    pierce with a pointed object; make a hole into
    pierce with many holes
    wear or cut gutters into
    prick, prickle
    make a small hole into, as with a needle or a thorn
    penetrate or cut, as with a knife
    pierce or penetrate or puncture with something pointed
    pierce with a thrust using a pointed instrument
    pierce with a wooden pin or knock or thrust a wooden pin into
    break up, pick
    attack with or as if with a pickaxe of ice or rocky ground, for example
    perforate, punch
    make a hole into or between, as for ease of separation
    center punch
    make a small hole in something as a guide for a drill
    empale, impale, spike, transfix
    pierce with a sharp stake or point
    horn, tusk
    stab or pierce with a horn or tusk
    wound by piercing with a sharp or penetrating object or instrument
    bite, prick, sting
    deliver a sting to
    dip, douse, dunk, plunge, souse
    immerse briefly into a liquid so as to wet, coat, or saturate
    plunge (one's hand or a receptacle) into a container
    immerse in a disinfectant solution
    submerge, submerse
    put under water
    submerge in a liquid
    plunge or bury (a knife or sword) in flesh
    pierce with a lance, as in a knights' fight
    soak through, sop
    be or become thoroughly soaked or saturated with a liquid
    pierce in order to draw a liquid from
    pass into or through by filtering or permeating
    cause (a liquid) to enter by penetrating the interstices
    type of:
    come in, enter, get in, get into, go in, go into, move into
    to come or go into
  2. verb
    spread or diffuse through
    “music penetrated the entire building”
    synonyms: diffuse, imbue, interpenetrate, permeate, pervade, riddle
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    spiritise, spiritize
    imbue with a spirit
    type of:
    pass into or through, often by overcoming resistance
  3. verb
    make one's way deeper into or through
    “The hikers did not manage to penetrate the dense forest”
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    type of:
    advance, go on, march on, move on, pass on, progress
    move forward, also in the metaphorical sense
  4. verb
    insert the penis into the vagina or anus of
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    type of:
    enter, infix, insert, introduce
    put or introduce into something
  5. verb
    enter a group or organization in order to spy on the members
    synonyms: infiltrate
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    type of:
    fall in, get together, join
    become part of; become a member of a group or organization
  6. verb
    come to understand
    synonyms: bottom, fathom
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    type of:
    know and comprehend the nature or meaning of
  7. verb
    become clear or enter one's consciousness or emotions
    “she was penetrated with sorrow”
    synonyms: click, come home, dawn, fall into place, get across, get through, sink in
Word Family

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