A chemical, biological, radiological, nuclear, or other weapon that is designed to cause death or serious injury to large numbers of civilians.(noun)
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Use "weapon of mass destruction" in a sentence
"Similarly, the congressionally authorized Commission on the Prevention of Weapons of Mass Destruction Proliferation and Terrorism issued a report in December 2008 that concluded: “It is more likely than not that a weapon of mass destruction will be used in a terrorist attack somewhere in the world by the end of 2013.”"