Affectedly dainty (4)
I believe the answer is:
twee
'affectedly dainty' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for twee that I've seen before include "Affectedly dainty or refined" , "Affectedly dainty or quaint" , "Affectedly pretty" , "Sentimentally sweet" , "Rather too pretty" .)