As a noun, it means a newly compiled version of the product. Projects will produce many internal builds before the one that is shipped to customers. Synonyms: baseline, slice.
The act of compiling the level so that it can perform all of the necessary precalculations such as lighting, path generation, and resolving geometry. Also known as Rebuilding, - The version of the Unreal Editor. For example: “UT2K3 uses the 2136 Build of the Engine. For more information on the various Builds of the Unreal Engine, see the UnrealFamilyTree document.