fusion
fu.sion \'fyu:-zh*n\ n [L fusion-, fusio, fr. fusus, pp.] often attrib 1a: the act or process of liquefying or rendering plastic by heat 1b: the liquid or plastic state induced by heat 2: a union by melting : as 2a: a merging of diverse elements into a unified whole 2b: a political partnership : COALITION 2c: the union of atomic nuclei to form heavier nuclei resulting in the rele ase of enormous quantities of energy when certain light elements unite