electromagnetic pulsen. Abbr. EMP1. The pulse of intense electromagnetic radiation generated by a nuclear explosion.2. A short-duration, broadband, high-intensity emission of electromagnetic energy, such as lightning.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.electromagnetic pulse n 1. (General Physics) a surge of electromagnetic radiation, esp one resulting from a nuclear explosion, which can disrupt electronic devices and, occasionally, larger structures and equipment. Often abbreviated to: EMP 2. (Arms & Armour (excluding Firearms)) a surge of electromagnetic radiation, esp one resulting from a nuclear explosion, which can disrupt electronic devices and, occasionally, larger structures and equipment. Often abbreviated to: EMP Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014electromagnetic pulseThe electromagnetic radiation from a strong electronic pulse, most commonly caused by a nuclear explosion that may couple with electrical or electronic systems to produce damaging current and voltage surges. Also called EMP. See also electromagnetic radiation.Dictionary of Military and Associated Terms. US Department of Defense 2005.