fifth columnist

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fifth column

A clandestine subversive organization working within a country to further an invading enemy's military and political aims.

[First applied in 1936 to rebel sympathizers inside Madrid when four columns of rebel troops were attacking that city.]

fifth col′um·nism (kŏl′əm-nĭz′əm) n.
fifth columnist n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.fifth columnist - a member of a clandestine subversive organization who tries to help a potential invader
fifth column, Trojan horse - a subversive group that supports the enemy and engages in espionage or sabotage; an enemy in your midst
traitor, treasonist - someone who betrays his country by committing treason
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

fifth columnist

nappartenente m/f alla quinta colonna
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995
References in periodicals archive ?
Of course, Liverpool once had its own town walls to support its castle, only breached by Prince Rupert's royalist army in 1644 after inside 'fifth columnist' help.
Osborne - known as "a Fifth columnist for Beijing" in Brussels - has been courting Chinese investment to build new nuclear power stations and the publicly subsidised Hinkley Point.
Our very own Fifth Columnist neocons, the Kristols, Abramses, Wolfowitzes, Perles, Feiths, Frums, and other such scummy types, are still being listened to by naive Americans instead of being silenced for their criminal propagandizing leading up to war.
I know there's a fifth columnist under there somewhere.
Antonio Trillanes IV denounced Senate President Juan Ponce Enrile as a "lackey" of former President Gloria Macapagal-Arroyo; Enrile countered that Trillanes was a fifth columnist and a coward.
<![CDATA[ You are a fifth columnist, National Union Knesset Member Uri Ariel accused Arab MK Taleb El-Sana, who replied, "You are a miserable wretch.
The fifth columnist was less the actual traitor than the "passive non-resister, a man unsure of himself and of his world," as one contemporary observer wrote.
Abdul Aziz, a Liberal Democrat Birmingham city councillor, has been sacked by his party on the grounds that he is alleged to be a Labour fifth columnist.
NOW the truth can be told: one of Saddam's body agents is a fifth columnist. You'll know him as Captain Haddock, Tintin's pal