Fine fellow Moray well-bred (7)
I believe the answer is:
genteel
'well-bred' is the definition.
(I've seen this before)
'fine fellow moray' is the wordplay.
'fine fellow' becomes 'gent' (I've seen this in another clue).
'moray' becomes 'eel' (I've seen this in another clue).
'gent'+'eel'='GENTEEL'
(Other definitions for genteel that I've seen before include "Fashionable" , "Suited to polite society" , "Politely refined" , "Affectedly polite and refined" , "Artificially polite" .)