Triangular scarf (5)
I believe the answer is:
fichu
'triangular scarf' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fichu that I've seen before include "Triangular shawl round shoulders and neck" , "Eighteenth-century woman's light scarf" , "Triangular cape" , "Lace shawl" , "Woman's small shawl or scarf" .)