Curiously desire nice divorce (6,4)
I believe the answer is:
decree nisi
'divorce' is the definition.
(I've seen this before)
'curiously desire nice' is the wordplay.
'curiously' is an anagram indicator.
'desire'+'nice'='desirenice'
'desirenice' is an anagram of 'DECREE NISI'.
(Other definitions for decree nisi that I've seen before include "Provisional divorce document" , "court order" , "Separation agreement" , "Judicial order" , "Provisional divorce order" .)