Public art (7)
I believe the answer is:
oratory
'public art' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for oratory that I've seen before include "Place for private prayer" , "formal speech" , "Gift of the gab" , "Formal speech-making, could be pompous" , "Art or skill of public speaking" .)