Noise of a bat (6)
I believe the answer is:
racket
I believe this is a double definition.
'noise' is the first definition.
(racket is a kind of noise)
'a bat' is the second definition.
(thesaurus)
'of' acts as a link.
(Other definitions for racket that I've seen before include "fiddle" , "produced at Wimbledon" , "Unpleasant din" , "Unpleasant noise, bat" , "See 1" .)