Bagpiper's skirt (4)
I believe the answer is:
kilt
'bagpiper's skirt' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for kilt that I've seen before include "Tartan skirt worn in Scotland" , "Scottish garb" , "Scotsman's attire" , "Scotsman's garb" , "Highland garb" .)