Wedding dress feature (5)
I believe the answer is:
train
'wedding dress feature' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for train that I've seen before include "Exercise in preparation for some event" , "School, educate" , "Long back section of a gown that's drawn along the floor" , "Number of animals moving in a line, like camels" , "union's lengthy item" .)