Wiktionary
n. Set of methodologies for fusing information coming from different, and sometimes non homogeneous, sources. The result of fusion is a qualitatively different knowledge always referred to a context.
Wikipedia
Data fusion is the process of integration of multiple data and knowledge representing the same real-world object into a consistent, accurate, and useful representation.
Data fusion processes are often categorized as low, intermediate or high, depending on the processing stage at which fusion takes place. Low level data fusion combines several sources of raw data to produce new raw data. The expectation is that fused data is more informative and synthetic than the original inputs.
For example, sensor fusion is also known as (multi-sensor) data fusion and is a subset of information fusion.
Usage examples of "data fusion".
The technologies that will be important in this area go beyond the data fusion algorithms currently in place and should leverage heavily off of technologies in fields such as computer image generation, virtual reality, and advanced simulation.