Note Pavarotti possibly heard? (6)
I believe the answer is:
tenner
'note' is the definition.
(a ten pound sterling bank note)
'pavarotti possibly heard?' is the wordplay.
'pavarotti possibly' becomes 'tenor' (Luciano Pavarotti of the Three Tenors).
'heard?' indicates a 'sounds like' (homophone) clue.
'tenor' is a homophone of 'TENNER'.
(Other definitions for tenner that I've seen before include "British note" , "Note - sounds like singer" , "British banknote" , "Note featuring Charles Darwin?" , "Monetary note" .)