What is the right word (verb) for a process of adding more details to something that's already been defined?
UPDATE:
Thank you for your answers!
The precise context is as follows:
I have a base entity which describes a whatever (very general) camera that has a few parts which are whatever lens, batteries, memory cards etc. This is what I referred to as "something that's already been defined". Now, I need to define a very real camera which is 'D700 Nikon' that has specific lens, batteries, etc. So I take my general definition and create a new definition by adding more details specific to the 'D700 Nikon' camera.
So the question is: what am I doing with the base definition?