Repetition from speech organiser (4)
I believe the answer is:
echo
'repetition' is the definition.
(I know that echo is a type of imitation)
'from speech organiser' is the wordplay.
'from' says the answer is hidden in the clue.
'ECHO' is hidden within 'speech organiser'.
(Other definitions for echo that I've seen before include "Noise heard again" , "Say again or imitate" , "Reflected radar beam" , "Greek nymph, spurned by Narcissus, who pined away until only her voice remained" , "Sound heard before" .)