Affluent banks in Madrid bagging working capital (8)
I believe the answer is:
richmond
'capital' is the definition.
(state capital of Virginia)
'affluent banks in madrid bagging working' is the wordplay.
'affluent' becomes 'rich' (similar in meaning).
'banks in' means to remove the middle letters (the edges or banks of the word).
'bagging' indicates putting letters inside (bag can mean to take or obtain).
'working' becomes 'on' (e.g. a machine is working or on).
'madrid' with its middle removed is 'md'.
'md' placed around 'on' is 'mond'.
'rich'+'mond'='RICHMOND'
(Other definitions for richmond that I've seen before include "Yorkshire town close to Catterick garrison" , "US state capital" , "Capital of Virginia, USA" , "Thameside town" , "Sweet lass of - Hill" .)