- to filter into or through; permeate.
- to cause to pass in by filtering.
- to move into (an organization, country, territory, or the like) surreptitiously and gradually, especially with hostile intent: The troops infiltrated the enemy lines.
- to pass a small number of (soldiers, spies, or the like) into a territory or organization clandestinely and with hostile or subversive intent: The intelligence agency infiltrated three spies into the neighboring country.
- to pass into or through a substance, place, etc., by or as by filtering.
- Pathology. to penetrate tissue spaces or cells.
- something that infiltrates.
- Pathology. any substance penetrating tissues or cells and forming a morbid accumulation.
Origin of infiltrate
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for infiltrator
Nor it just the Post—"infiltrator" is also used by the Israeli news site Ynet and by the Religious Zionist Arutz Sheva.Infiltrated by History
May 30, 2012
One, that he might possibly have been an infiltrator working for the FBI?Warren Commission (10 of 26): Hearings Vol. X (of 15)
The President's Commission on the Assassination of President Kennedy
- to undergo or cause to undergo the process in which a fluid passes into the pores or interstices of a solid; permeate
- military to pass undetected through (an enemy-held line or position)
- to gain or cause to gain entrance or access surreptitiouslythey infiltrated the party structure
- something that infiltrates
- pathol any substance that passes into and accumulates within cells, tissues, or organs
- pathol a local anaesthetic solution injected into the tissues to cause local anaesthesia
C18: from in- ² + filtrate
Word Origin and History for infiltrator
Online Etymology Dictionary, © 2010 Douglas Harper
- To cause a liquid to permeate a substance by passing through its interstices or pores.
- To permeate a porous substance with a liquid or gas.
- An abnormal substance that accumulates gradually in cells or body tissues.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.