| FIRSTSTRIKE | Initial use of nuclear weapons |
| NPT | International agreement aimed at halting the spread of nuclear weapons and promoting peaceful use of nuclear energy.(abbvr) (3) |
| STAFFNOTATION | Employees, people accepting Old Trafford's initial use of lines to mark pitch (5,8) |
| MRI | The use of nuclear magnetic resonance of protons to produce proton density images. |
| ATOMICENERGYACT | Legislation that promoted peaceful uses of nuclear resources |
| ICBM | Shorthand for a type of long-range missile, used for delivery of nuclear weapons (4) |
| PROLIFERATION | Increase (of nuclear weapons) (13) |
| DETERRENCE | Eg, possession of nuclear weapons |
| TESTBAN | Agreement between nations to forgo trials of nuclear weapons (4,3) |
| NODDYSUIT | Clothing that protects wearer against physical effects of nuclear weapons (5,4) |
| NONPROLIFERATIONTREATY | International agreement negotiated in the 1960s, intended to prevent the spread of nuclear weapons |
| ROTBLAT | Sir Joseph, Polish-born physicist noted as a critic of nuclear weapons (7) |
| KILOTON | Unit traditionally used to rate the energy output, and hence destructive power, of nuclear weapons, whose symbol is kt |
| BIKINI | Travelling by bicycle endlessly on island site of nuclear weapons tests (6) |
| ATOMICAGE | A cat enclosure I entered since the invention of nuclear weapons (6,3) |
| NARROW | Source of nuclear weapon strictly limited (6) |
| LANCE | Delicate material encasing head of nuclear weapon (5) |
| HBOMB | Type of nuclear weapon (1-4) |
| GROUNDZERO | Land directly under explosion of nuclear weapon in the air (6,4) |
| NEUTRON | A --- bomb is a type of nuclear weapon which causes little blast or long-term radioactive contamination (7) |
