Wall scribblings (8)
I believe the answer is:
graffiti
'wall scribblings' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for graffiti that I've seen before include "Scribbled drawings in public places" , "Mural artwork" , "Scribblings on the walls of buildings" , "Scrawls on walls - fair gift" , "Words or drawings scrawled on walls" .)