Sax accessory (4)
I believe the answer is:
reed
'sax accessory' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reed that I've seen before include "Marsh plant for deer" , "Vibrating part of some instruments" , "Vibrator in the mouthpiece of a wind instrument" , "Type of grass" , "Stalk" .)