Rubbish very loudly placed in heap (6)
I believe the answer is:
piffle
'rubbish' is the definition.
(thesaurus)
'very loudly placed in heap' is the wordplay.
'very loudly' becomes 'ff'.
'placed in' indicates putting letters inside (I've seen this in other clues).
'heap' becomes 'pile' ('pile' can be a synonym of 'heap').
'ff' placed inside 'pile' is 'PIFFLE'.
(Other definitions for piffle that I've seen before include "Balderdash" , "Twaddle" , "Informal nonsense, worthless talk" , "Hogwash" , "Stuff and nonsense" .)