Discard support (5)
I believe the answer is:
sling
I believe this is a double definition.
'discard' is the first definition.
'support' is the second definition.
(sling is a kind of support)
(Other definitions for sling that I've seen before include "Injured-arm support" , "Simple weapon; throw" , "throwing implement like catapult" , "Arm bandage; hurl" , "Primitive weapon" .)