Display unrestrained creative work over restaurant (9)
I believe the answer is:
trattoria
'restaurant' is the definition.
(I've seen this before)
'display unrestrained creative work over' is the wordplay.
'display' becomes 'air' (I've seen this before).
'unrestrained' becomes 'ott' (abbreviation for 'over the top').
'creative work' becomes 'art'.
'over' is a reversal indicator.
'air'+'ott'+'art'='airottart'
'airottart' back-to-front is 'TRATTORIA'.
(Other definitions for trattoria that I've seen before include "where Italians eat" , "Italian restaurant" , "Place to eat" , "Italian eating establishment" .)