Fusion typically refers to the merging of two or more entities into a single one:
- In physics and technology
- In biology and medicine
- In social sciences
- In linguistics, fusion is the process of combining morphemes into molecules via sandhi, deletion, etc.
- In sociology, fusion is a term used in reference to the joining of cultural entities:
- In politics, electoral fusion is an arrangement between political parties to pool votes for a single candidate.
- In culture
- In history
- Fusion is the name given to several reformist political slates formed to fight elections in New York City in the period 1880-1940, generally because it was believed that the Republican party alone could not win in the city.
Fusion may also refer to the names for commercial products: