Cleanup: "Dupli" to "Instance".
Following the T56648: Blender 2.8: Naming Conventions
Duplication -> Instancing
Status: Done
In the context of Particle instances, Collection instances, and the old DupliVerts/DupliFaces, which also creates instances.
Instances are a unique feature that saves memory, which isn't communicated by the term 'duplication'.
Actually duplicating objects and items should still use the term 'duplicate'.