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Definition of "infiltrate" []

  • To pass (troops, for example) surreptitiously into enemy-held territory. (verb-transitive)
  • To penetrate with hostile intent: infiltrate enemy lines; terrorists that had infiltrated the country. (verb-transitive)
  • To enter or take up positions in gradually or surreptitiously, as for purposes of espionage or takeover: infiltrated key government agencies with spies. (verb-transitive)
  • To cause (a liquid, for example) to permeate a substance by passing through its interstices or pores. (verb-transitive)
  • To permeate (a porous substance) with a liquid or gas. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "infiltrate" in a sentence
  • "This first episode picks up where "Half-Life 2" ended: the towering alien fortress you and female friend Alyx managed to infiltrate is about to blow in a very big way."
  • "Don't want to reveal my plan but is the word infiltrate appropriate?"
  • ""The use of the word infiltrate to refer to a child reeks of small minded bigotry.""