Emulator (8)
I believe the answer is:
imitator
'emulator' is the definition.
(I know that emulator can be written as imitator)
This is all the clue.
(Other definitions for imitator that I've seen before include "parrot" , "Copier (of another)" , "Someone copying the behaviour of another" , "One who mimics or emulates" , "follower" .)