weapon of mass destruction
noun /ˌwepən əv ˌmæs dɪˈstrʌkʃn/
  /ˌwepən əv ˌmæs dɪˈstrʌkʃn/
 (abbreviation WMD)
- a weapon such as a nuclear weapon, a chemical weapon or a biological weapon that can destroy large areas and kill many people
- states developing weapons of mass destruction