Group of established artists in squabble over street art (8)
I believe the answer is:
graffiti
'street art' is the definition.
(I know this)
'group of established artists in squabble over' is the wordplay.
I cannot quite see how this works, but
'artists' could be 'ra' (Royal Academy of the Arts) and 'ra' is present in the answer.
'group of' could be 'g' (eg the G7 nations, Group of Seven) and 'g' is located in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for graffiti that I've seen before include "Unwanted writing in public places" , "Wall-scribblings" , "Wall scribblings" , "act of vandalism?" , "Mural artwork" .)