a person who spies on a country while pretending to spy for it.
a spy in the service of two rival countries, companies, etc.
Origin of double agent
First recorded in 1930–35
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a spy employed by two mutually antagonistic countries, companies, etc
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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