Milestone
Also said as Deliverable, Milestone build
An agreed date when a defined piece of work must be delivered and checked. With a publisher, passing one is commonly how the next part of the money gets paid.
Without checkpoints, a project can look fine right up until the end. Milestones force an honest look at the real game on a known day, while there is still time to change course.
Say it
“Milestone 4 is 1 March. It means three levels playable start to finish on a console dev kit with no crashes. If that is not true on the day, we report it as a miss.”
Not to be confused with deadline
A deadline is any date something is due. A milestone is a checkpoint with an agreed definition of done, and for a funded studio it often has money attached.