(physics) A nuclear reaction in which a large nucleus splits into smaller ones, sometimes accompanied by the simultaneous release of energy.

A family unit consisting of two parents (traditionally a mother and a father) and their children.

A process such as the fission of an atomic nucleus, or the fusion of one or more atomic nuclei and/or subatomic particles in which the number of protons and/or neutrons in a nucleus changes; the reaction products may contain a different element or a different isotope of the same element.

A weapon that derives its energy from the nuclear reactions of either fission or fusion.

The age in which nuclear energy and nuclear weapons were developed.

A predicted drop in global temperature following a nuclear war due to dust in the upper atmosphere reducing sunlight reaching the ground.

(medicine) a cataract that affects just the dense inner part of the lens

the explosion of a nuclear weapon at such an altitude that the fireball remains above the ground

A limited-yield nuclear weapon delivered using an artillery shell.

A proposed aircraft that would be powered by nuclear energy.