Works in a gallery (4,3)
'works in a gallery' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for art that I've seen before include "Beautiful or significant products of human creativity" , "''... is long and life is short''" , "Trickery" , "Drawing" , "Works of creative imagination" .)
(Other definitions for fine art that I've seen before include "In after (anag) - painting, sculpture etc" , "aesthetic production" , "Canvas perhaps" , "Such as painting, sculpture or architecture" , "Thing of beauty" .)
(Other definitions for oils that I've seen before include "Reduces friction" , "Liquids for frying" , "art exhibits perhaps" , "Soil, oddly, used by painters" , "7's paint medium" .)