Cultured chap may mangle net terribly (9)
I believe the answer is:
gentleman
'cultured chap' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'mangle net terribly' is the wordplay.
'terribly' indicates an anagram.
'mangle'+'net'='manglenet'
'manglenet' anagrammed gives 'GENTLEMAN'.
'may' is the link.
Can you help me to learn more?
(Other definitions for gentleman that I've seen before include "Polite, kind or upper-class fellow" , "trustworthy type" , "Courteous chap" , "A man of refinement" , "-'s -; - farmer" .)