Foreign banker once more repelled artist (7)
I believe the answer is:
niagara
'foreign banker' is the definition.
The definition suggests a singular noun which matches the answer.
'once more repelled artist' is the wordplay.
'once more' becomes 'again' (synonyms).
'repelled' says the letters should be written in reverse.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'again' backwards is 'niaga'.
'niaga'+'ra'='NIAGARA'
Can you help me to learn more?
(Other definitions for niagara that I've seen before include "Canadian waterfall" , "Famous Falls once walked by Blondin" , "Large water falls" , "Famous waterfalls" , "River forming part of US-Canada border" .)