the definition for fusion
noun. The definition of fusion is the act of melting or blending two or more separate things into one. An example of fusion is creating a dinner that combines Indian and Japanese elements.1  a fusing or melting together. 2  the union of different things by or as if by melting; blending; coalition: a fusion of political parties. Physics A nuclear reaction in which atomic nuclei combine to form more massive nuclei with the simultaneous release of energy. 2  Music that blends jazz elements and the heavy repetitive rhythms of rock. 3  Also called jazz-fusion, jazz-rock.
fusion-a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy. nuclear fusion, nuclear fusion reaction.. the act or process of fusing or the state of being fused. 2. that which is fused; the result of fusing: A ballet production is the fusion of many talents. 3. a. a coalition of political parties or factions. b. (cap.) the body resulting from such a coalition.