What about cold duck or parrot? (4)
I believe the answer is:
echo
'parrot?' is the definition.
(both can mean to imitate or copy)
'what about cold duck' is the wordplay.
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'about' is an insertion indicator.
'cold' becomes 'C' (eg on taps).
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'eh' enclosing 'c' is 'ech'.
'ech'+'o'='ECHO'
'or' is the link.
(Other definitions for echo that I've seen before include "Sound following" , "ring" , "Return of sound waves" , "Close imitation" , "Languishing nymph" .)