Repeat mindlessly (6)
I believe the answer is:
parrot
'repeat mindlessly' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for parrot that I've seen before include "Unintelligent imitator" , "Copycat who does not understand words or acts imitated" , "Long John Silver's Captain Flint" , "Chant" , "Bright tropical bird" .)