Archetype, master copy (8)
I believe the answer is:
original
I believe this is a double definition.
'archetype' is the first definition.
(I know that archetype can be written as original)
'master copy' is the second definition.
(synonyms)
(Other definitions for original that I've seen before include "- - sin" , "derivation" , "Primitive, earliest" , "Phototype" , "Archetype,master copy" .)