Love affair rocking Cremona (7)
I believe the answer is:
romance
'love affair' is the definition.
(I know that love affair can be written as romance)
'rocking cremona' is the wordplay.
'rocking' indicates anagramming the letters.
'cremona' anagrammed gives 'ROMANCE'.
(Other definitions for romance that I've seen before include "mysterious quality" , "Language group; love affair" , "Affair of the heart" , "Cameron (anag) - love story" , "Feeling of mystery; love affair" .)