Part of a makeshift swing (4)
I believe the answer is:
tire
'part of a makeshift swing' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tire that I've seen before include "Get weary" , "Exhaust" , "Grow weary of rite" , "Feel in need of rest" , "Become weary" .)