Standard Lemma guide

infiltrate

noun · verb · 12 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • UK: /ˈɪnfɪltɹeɪt/
  • US: /ˈɪnfəltɹeɪt/
  • US: /ɪnˈfɪltɹeɪt/
  • US: Recorded audio is listed in the source snapshot.
  • CMU ARPABET: IH1 N F IH0 L T R EY2 T Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.

1

noun

Meaning 1

Any undesirable substance or group of cells that has made its way into part of the body.

Definition source: English Wiktionary via Wiktextract

Topics: medicine, pathology, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

verb

Meaning 2

To surreptitiously penetrate, enter or gain access to.

Definition source: English Wiktionary via Wiktextract

Usage: ambitransitive

Examples

  • The spy infiltrated the high-tech company and stole many secrets.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

verb

Meaning 3

To cause to penetrate in this way.

Definition source: English Wiktionary via Wiktextract

Usage: transitive

Examples

  • The agency infiltrated several spies into the company.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

verb

Meaning 4

To pass through something by filtration.

Definition source: English Wiktionary via Wiktextract

Usage: ambitransitive

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

5

verb

Meaning 5

To cause (a liquid) to pass through something by filtration.

Definition source: English Wiktionary via Wiktextract

Usage: transitive

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

6

verb

Meaning 6

To invade or penetrate a tissue or organ.

Definition source: English Wiktionary via Wiktextract

Usage: ambitransitive

Topics: medicine, sciences

Examples

  • High-grade tumors often infiltrate surrounding structures.
  • In certain conditions, immune cells may infiltrate into the cerebrospinal fluid.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

7

verb

Meaning 7

To send (soldiers, spies, etc.) through gaps in the enemy line.

Definition source: English Wiktionary via Wiktextract

Usage: transitive

Topics: government, military, politics, war

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: exfiltrate

8

verb

Meaning 8

To move from a vein, remaining in the body.

Definition source: English Wiktionary via Wiktextract

Usage: intransitive

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

9

verb

Meaning 9

pass through an enemy line; in a military conflict

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: pass through

Antonyms: none provided

Broader terms: pass, go through, go across

10

verb

Meaning 10

pass into or through by filtering or permeating

Definition source: Princeton WordNet 3.0

Examples

  • the substance infiltrated the material

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: percolate, sink in, permeate, filter

11

verb

Meaning 11

cause (a liquid) to enter by penetrating the interstices

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: percolate, sink in, permeate, filter

12

verb

Meaning 12

enter a group or organization in order to spy on the members

Definition source: Princeton WordNet 3.0

Examples

  • The student organization was infiltrated by a traitor

Meaning relationships

Synonyms: penetrate

Antonyms: none provided

Broader terms: join, fall in, get together

History

Etymology

From Middle English infiltrate (adjective), from Medieval Latin infiltrātus, from infiltrō.

Across languages

Translations

55 source translations are retained for this English entry.

  • German: Infiltrat — infiltrate
  • Hungarian: infiltrátum — infiltrate
  • Hungarian: beszűrődés — infiltrate
  • Indonesian: infiltrat — infiltrate
  • Romanian: infiltrat — infiltrate
  • Afrikaans: infiltreer — to surreptitiously penetrate, enter or gain access
  • Catalan: infiltrar — to surreptitiously penetrate, enter or gain access
  • Czech: proniknout — to surreptitiously penetrate, enter or gain access
  • Esperanto: infiltri — to surreptitiously penetrate, enter or gain access
  • Finnish: soluttautua — to surreptitiously penetrate, enter or gain access
  • French: infiltrer — to surreptitiously penetrate, enter or gain access
  • German: infiltrieren — to surreptitiously penetrate, enter or gain access
  • German: unterwandern — to surreptitiously penetrate, enter or gain access
  • Greek: διεισδύω (dieisdýo) — to surreptitiously penetrate, enter or gain access
  • Hindi: घुसपैठ करना (ghuspaiṭh karnā) — to surreptitiously penetrate, enter or gain access
  • Hindi: पैठना (paiṭhnā) — to surreptitiously penetrate, enter or gain access
  • Hungarian: beszivárog — to surreptitiously penetrate, enter or gain access
  • Ido: infiltrigar — to surreptitiously penetrate, enter or gain access
  • Irish: insíothlaigh — to surreptitiously penetrate, enter or gain access
  • Irish: síothlaigh isteach — to surreptitiously penetrate, enter or gain access
  • Italian: infiltrare — to surreptitiously penetrate, enter or gain access
  • Japanese: 潜入する (sennyū suru) — to surreptitiously penetrate, enter or gain access
  • Māori: ngoto — to surreptitiously penetrate, enter or gain access
  • Persian: نفوذ کردن (nofuz kardan) — to surreptitiously penetrate, enter or gain access
  • Russian: проса́чиваться (prosáčivatʹsja) — to surreptitiously penetrate, enter or gain access
  • Russian: просочи́ться (prosočítʹsja) — to surreptitiously penetrate, enter or gain access
  • Russian: проника́ть (pronikátʹ) — to surreptitiously penetrate, enter or gain access
  • Russian: прони́кнуть (proníknutʹ) — to surreptitiously penetrate, enter or gain access
  • Sicilian: nfirtrari — to surreptitiously penetrate, enter or gain access
  • Spanish: infiltrarse — to surreptitiously penetrate, enter or gain access
  • Swedish: infiltrera — to surreptitiously penetrate, enter or gain access
  • Thai: แทรกซึม — to surreptitiously penetrate, enter or gain access
  • Bulgarian: процеждам (proceždam) — to cause a fluid to pass through a substance by filtration
  • Bulgarian: просмуквам се (prosmukvam se) — to cause a fluid to pass through a substance by filtration
  • Catalan: infiltrar — to cause a fluid to pass through a substance by filtration
  • Finnish: suodattaa — to cause a fluid to pass through a substance by filtration
  • Irish: insíothlaigh — to cause a fluid to pass through a substance by filtration
  • Irish: síothlaigh isteach — to cause a fluid to pass through a substance by filtration
  • Italian: filtrare — to cause a fluid to pass through a substance by filtration
  • Japanese: 浸透させる (shintō saseru) — to cause a fluid to pass through a substance by filtration
  • Manx: yn-heel — to cause a fluid to pass through a substance by filtration
  • Sicilian: firtrari — to cause a fluid to pass through a substance by filtration
  • Spanish: infiltrar — to cause a fluid to pass through a substance by filtration
  • Turkish: süzmek — to cause a fluid to pass through a substance by filtration
  • Belarusian: пранікаць у тыл праціўніка (pranikacʹ u tyl praciwnika) — to send soldiers through gaps in the enemy line
  • Belarusian: пранікнуць у тыл праціўніка (praniknucʹ u tyl praciwnika) — to send soldiers through gaps in the enemy line
  • Finnish: soluttaa — to send soldiers through gaps in the enemy line
  • Italian: infiltrare — to send soldiers through gaps in the enemy line
  • Japanese: 潜入させる (sennyū saseru) — to send soldiers through gaps in the enemy line
  • Polish: infiltrować — to send soldiers through gaps in the enemy line
  • Polish: zinfiltrować — to send soldiers through gaps in the enemy line
  • Russian: проникать в тыл противника (pronikatʹ v tyl protivnika) — to send soldiers through gaps in the enemy line
  • Russian: проникнуть в тыл противника (proniknutʹ v tyl protivnika) — to send soldiers through gaps in the enemy line
  • Sicilian: nfirtrari — to send soldiers through gaps in the enemy line
  • Thai: สอดแทรก — to send soldiers through gaps in the enemy line