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electronic countermeasures

plural noun
  1. the use of electronic technology to jam and deceive enemy radars, especially those used for air defense and interception. Abbreviation: ECM

Origin of electronic countermeasures

First recorded in 1965–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for electronic countermeasures

electronic countermeasures

pl n
  1. military (in electronic warfare) actions intended to interfere with an enemy's use of electromagnetic radiation equipment
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