For real crime, Capone cleared out bank (9)
I believe the answer is:
sincerely
'for real' is the definition.
Both the definition and answer are adverbs. Maybe you can see an association between them that I can't see?
'crime capone cleared out bank' is the wordplay.
'crime' becomes 'sin'.
'cleared out' says to hollow out the word (remove centre letters).
'bank' becomes 'rely' (to bank on something is to rely on it).
'capone' with its centre removed is 'ce'.
'sin'+'ce'+'rely'='SINCERELY'
Can you help me to learn more?
(Other definitions for sincerely that I've seen before include "In good faith" , "In a genuine way" , "How one may complete letter" , "Genuinely, honestly" , "With genuine feelings" .)