Parrot in part of London house (4)
I believe the answer is:
echo
'parrot' is the definition.
(thesaurus)
'part of london house' is the wordplay.
'part of london' becomes 'ec'.
'house' becomes 'ho' (abbreviation for house).
'ec'+'ho'='ECHO'
'in' acts as a link.
(Other definitions for echo that I've seen before include "Reflected radar beam" , "Ape" , "Greek nymph, spurned by Narcissus, who pined away until only her voice remained" , "Send back" , "Evocation" .)