nuclear energy

The Simple English Wikipedia has an article on: Nuclear weapon A nuclear weapon is a weapon that uses nuclear energy to cause an explosion.

an atom. Japan relies mainly on nuclear power (atomic energy) generation for its energy needs. The US has more nuclear weapons than any other country.

(countable) A nuclear bomb is a kind of bomb that uses the energy made from fission or fusion nuclear reactions. Synonyms: atomic bomb, A-bomb, atom bomb

A fusion bomb is an atomic bomb that uses nuclear fusion as a source of energy. hydrogen bomb H-bomb thermonuclear bomb

physics, nuclear fusion is when the nuclei of two or more atoms come together to make one new, heavier nucleus. Fusion reactions make a lot of energy. fuse