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Related to fifth column: fifth estate
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.
1. (Historical Terms) (originally) a group of Falangist sympathizers in Madrid during the Spanish Civil War who were prepared to join the four columns of insurgents marching on the city
2. any group of hostile or subversive infiltrators; an enemy in one's midst
fifth columnist n
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
1. a group of people who act traitorously and subversively out of a secret sympathy with an enemy of their country.
2. (originally) Franco sympathizers in Madrid during the Spanish Civil War: the insurgents had four columns marching on Madrid and a “fifth column” of supporters already in the city.
fifth′ col′umnist, n.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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|Noun||1.||fifth column - a subversive group that supports the enemy and engages in espionage or sabotage; an enemy in your midst|
social unit, unit - an organization regarded as part of a larger social group; "the coach said the offensive unit did a good job"; "after the battle the soldier had trouble rejoining his unit"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.