Slavish imitator (7)
I believe the answer is:
copycat
'slavish imitator' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for copycat that I've seen before include "Person (or crime) imitating another" , "Done in imitation" , "not the original one" , "Ape" , "One imitating another" .)