Fattened fowl a gang leader left unfinished (5)

I believe the answer is:

capon

'fattened fowl' is the definition.

'a gang leader left unfinished' is the wordplay.
'a gang leader' becomes 'capone' (Al Capone).
'left unfinished' means to remove the last letter.
'capone' with its last letter taken away is 'CAPON'.

(Other definitions for capon that I've seen before include "Castrated cock fowl" , "Castrated cock fattened for eating" , "one fattened specially" , "Male fowl fattened for eating" , "poultry?" .)

I've seen this clue in The Times.

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