Clerical garment
I believe the answer is:
alb
'clerical garment' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for alb that I've seen before include "Priests robe made in Balbriggan" , "the vicar might put on?" , "Cover" , "Long white robe worn by proest" , "Priest's long white sleeved vestment" .)