Neutron bomb

A neutron bomb is a nuclear weapon that releases a larger than usual fraction of its yield as neutron radiation. 20th-century human versions have nearly the same blast and thermal effects as a normal tactical nuclear weapon, but the radiation can kill enemy inside hardened targets (e.g. tanks) that would otherwise have survived. Alien versions may release a much higher fraction of their output as neutrons, killing organic life in a wide area without producing a large explosion.

On Skaro, neutron bombs were used in the neutronic war between the Dals and the Thals. (DW: The Daleks) These eventually caused the humanoid Daleks to mutate into the "machine Daleks". (TV21: Genesis of Evil)

The War Lords' Security Chief decided to use a neutron bomb to destroy the humans' resistance movement, but the Second Doctor saved them by transporting them in a SIDRAT to Central control. (DW: The War Games)

In the 1970s, the Third Doctor used a neutron bomb on the Moon to destroy the Daleks' base there. (TVC: The Disintegrator)