Dress designer finally gets an award (4)
I believe the answer is:
Here is my best explanation:
'dress' is the definition.
(robing is a kind of dressing)
'designer finally gets an award' is the subsidiary indication.
'finally' indicates one should take the final letters.
'gets' is a charade indicator (letters next to each other).
'an award' becomes 'obe' (I've seen this in other clues**).
The final letter of 'designer' is 'r'.
(Other definitions for robe that I've seen before include "Long loose garment or dressing gown", "Clerical garment", "Dressed buffalo hide", "Any loose flowing garment", "Clobber", "judge's garment", "Dress of office", "Formal vestment", "Loose or formal garment" and "Loose garment for Boer".)