Copy of paper (3)
I believe the answer is:
ape
'copy' is the definition.
(ape can mean to copy or imitate)
'of paper' is the wordplay.
'of' says the answer is hidden in the clue.
'APE' can be found hidden inside 'paper'.
(Other definitions for ape that I've seen before include "Wild animal" , "gorilla" , "Idiot" , "Take off" , "Mimic the primate" .)