A fellow’s eloquent and wealthy (8)
I believe the answer is:
affluent
'wealthy' is the definition.
(synonyms)
'a fellow's eloquent' is the wordplay.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'eloquent' becomes 'fluent' (synonyms).
'a'+'f'+'fluent'='AFFLUENT'
'and' is the link.
(Other definitions for affluent that I've seen before include "comfortable" , "Very well off, quite rich" , "Wealthy, rich" , "Well off, having plenty of money" , "Rich; flowing freely" .)