Genuine theft, real criminal (9)
I believe the answer is:
heartfelt
'genuine' is the definition.
(thesaurus)
'theft real criminal' is the wordplay.
'criminal' indicates an anagram.
'theft'+'real'='theftreal'
'theftreal' anagrammed gives 'HEARTFELT'.
(Other definitions for heartfelt that I've seen before include "With sincere passion" , "Most fervent in cardiac way" , "unfeigned sincerity" , "Kindly" , "Sincerely intended with strong feeling" .)