fusion - noun

an occurrence that involves the production of a union

the state of being combined into one body

the merging of adjacent sounds or syllables or words

a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy

the combining of images from the two eyes to form a single visual percept

correction of an unstable part of the spine by joining two or more vertebrae; usually done surgically but sometimes done by traction or immobilization

the act of fusing (or melting) together

fusion - thesaurus

coalition   merger   unification