fifth column

noun

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: so called in allusion to a statement in 1936 that the insurgents had four columns marching on Madrid and a fifth column of sympathizers in the city ready to rise and betray it.

fifth column

noun

1. (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 column

1. People willing to cooperate with an aggressor against their own country. The term originated in a remark by Francisco Franco , the Spanish dictator, that he was marching on Madrid with four columns of troops, and that there was a “fifth column” of sympathizers within the city ready to help.

Derived Forms

• fifth columnist, noun

Other Words From

• fifth columnist noun

Idioms and Phrases

A secret subversive group that works against a country or organization from the inside, as in The government feared that there was a fifth column working to oppose its policies during the crisis . This term was invented by General Emilio Mola during the Spanish Civil War in a radio broadcast on October 16, 1936, in which he said that he had una quinta columna (“a fifth column”) of sympathizers for General Franco among the Republicans holding the city of Madrid, and it would join his four columns of troops when they attacked. The term was popularized by Ernest Hemingway and later extended to any traitorous insiders.

Example Sentences

The interview is "really quite sad," Clinton continued, because it's a sign that some Americans at this moment "are like a fifth column from Vladimir Putin."

From Salon

They have also adopted the former president's conspiratorial rhetoric about the federal bureaucracy and civil service, which is now depicted as a national fifth column.

From Salon

The decree “deals a final blow to the fifth column within the country,” he added.

From Seattle Times

“This is a fifth column!” he wrote on social media, without naming names.

From New York Times

To vitalize a fifth column, they would create a large network of Nazi sympathizers working against the United States from within the United States.

From Literature