White rose treated differently (9)
I believe the answer is:
otherwise
'differently' is the definition.
(I've seen this before)
'white rose treated' is the wordplay.
'treated' is an anagram indicator.
'white'+'rose'='whiterose'
'whiterose' is an anagram of 'OTHERWISE'.
(Other definitions for otherwise that I've seen before include "Alternatively" , "As an alternative - like white rose" , "Differently - or else!" , "White rose (anag.)" , "In other respects or ways" .)