Denied having applied more polish (8)
I believe the answer is:
rebuffed
'denied' is the definition.
(thesaurus)
'applied more polish' is the wordplay.
I cannot quite understand how this works, but
'polish' could be 'buff' (buffing is a kind of polishing) and 'buff' is found within the answer.
The remaining letters 'reed' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'having' acts as a link.
Can you help me to learn more?
(Other definitions for rebuffed that I've seen before include "Abruptly rejected" , "Snubbed, slighted" , "Rejected ungraciously" , "Snubbed in contemptuous way" , "Snubbed, rejected unkindly" .)