Reproduce the usual rubbish (6)
I believe the answer is:
parrot
'reproduce' is the definition.
(thesaurus)
'usual rubbish' is the wordplay.
'usual' becomes 'par' (par is an average golf score).
'rubbish' becomes 'rot' (both can mean nonsense).
'par'+'rot'='PARROT'
'the' acts as a link.
(Other definitions for parrot that I've seen before include "Tropical bird to repeat mindlessly" , "Repeater" , "Imitative bird" , "Avian mimic" , "Raucous bird" .)