Move Whistler's new painting back (8)
I believe the answer is:
transfer
'move' is the definition.
(transferring is a kind of moving)
'whistler's new painting back' is the wordplay.
'whistler's' becomes 'ref's' (a referee blows a whistle).
'new' becomes 'n' (abbreviation as in New Testament NT).
'painting' becomes 'art' (painting is an art).
'back' is a reversal indicator.
'refs'+'n'+'art'='refsnart'
'refsnart' written backwards gives 'TRANSFER'.
(Other definitions for transfer that I've seen before include "Move, change (to new place)" , "Convey from one surface to another" , "Move something from one place to another" , "Move to another side or team" , "Hand, move, change, over" .)