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"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, Â§ 2902, 2009]
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).