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weapons of mass destruction

pl n
  1. nuclear, chemical, or biological weapons that can cause indiscriminate death or injury on a large scaleAbbreviation: WMD
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
Word Origin and History for weapons of mass destruction
n.

"nuclear, biological and chemical weapons" attested by 1946, apparently first used (in Russian) by the Soviets.

The terms "weapons of mass destruction" and "WMD" mean chemical, biological, and nuclear weapons, and chemical, biological, and nuclear materials used in the manufacture of such weapons. [United States Code: Title 50, "War and National Defense," chapter 43, § 2902, 2009]
Online Etymology Dictionary, © 2010 Douglas Harper
weapons of mass destruction in Culture

weapons of mass destruction

Weapons that can produce devastating results when delivered in a single strike. They include nuclear, chemical, and biological weapons.

Note

One of the great challenges of the twenty-first century will be to constrain the proliferation and use of such weapons, especially by terrorists (see terrorism).
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.