A fellow's smooth and rich (8)
I believe the answer is:
affluent
'rich' is the definition.
('affluent' can be similar in meaning to 'rich')
'a fellow's smooth' is the wordplay.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'smooth' becomes 'fluent' ('fluent' can be a synonym of 'smooth'**).
'a'+'f'+'fluent'='AFFLUENT'
'and' acts as a link.
(Other definitions for affluent that I've seen before include "comfortable" , "Rich; flowing freely" , "Well off, having plenty of money" , "Well-to-do, wealthy" , "Wealthy, rich" .)