The BABOK® v3 Guide describes this term as follows:
“The act of transformation in response to a need.”
This really reflects that the role of the business analysis is to facilitate the change to improve upon or to address a specific business need with specific activities and measures.
An example here could be when a new initiative is started to implement an automated payroll calculator. One of the change aspects could include business analysis activities that focus on business processes that need to be changed to facilitate the automated calculation rather than using the existing manual business processes.