Velocity, as a term used in project management, is defined as the measure of the productivity rate of the project team with respect to the produced, validated and accepted deliverables. It is usually measured within a pre-defined interval. It is also used in capacity planning to forecast the future work and tasks involved in a project.
It can be used as a tool by project managers to predict whether their team can deliver a similar work in the future provided that the conditions are the same. This allows project managers to predict the duration needed for the project team to finish the same task that they have already completed in the past.
Aside from predicting the rate of future work, many project managers want to increase the velocity of their team. Focusing on fast work cycles through iterations is often done where the product can be created quickly and also be reviewed by the stakeholders for consistency. Project managers can also switch gears to avoid wasting time while doing the project. This method requires creating a list of important lessons learned for future planning.
This term is defined in the 5th edition of the PMBOK.