Put up painting of leaf (5)
I believe the answer is:
folio
'leaf' is the definition.
(I know that leaf can be written as folio)
'put up painting of' is the wordplay.
'put up' says the letters should be written backwards.
'painting' becomes 'oil' (oil painting is a kind of painting).
'oil'+'of'='oilof'
'oilof' reversed gives 'FOLIO'.
(Other definitions for folio that I've seen before include "Four pages" , "Leaf of book - page number" , "large book" , "Leaf of paper" , "File" .)