| 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 n. 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. |
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.
fifth column
A secret subversive group that works against a country or organization from the inside, as in The right-to-life movement has established a fifth column among freedom-of-choice activists. 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.
fifth column
clandestine group or faction of subversive agents who attempt to undermine a nation's solidarity by any means at their disposal. The term is credited to Emilio Mola Vidal, a Nationalist general during the Spanish Civil War (1936-39). As four of his army columns moved on Madrid, the general referred to his militant supporters within the capital as his "fifth column," intent on undermining the loyalist government from within
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