GB dealer generates capital (8)
I believe the answer is:
belgrade
'capital' is the definition.
(capital of Serbia)
'gb dealer generates' is the wordplay.
'generates' indicates anagramming the letters.
'gb'+'dealer'='gbdealer'
'gbdealer' anagrammed gives 'BELGRADE'.
(Other definitions for belgrade that I've seen before include "Serbian city" , "Capital of former Yugoslavia" , "Capital city - large bed (anag)" , "Capital of Serbia and Montenegro" , "Balkan capital" .)