Winds up unnecessary contracts (7)
I believe the answer is:
needles
'winds up' is the definition.
(I've seen this before)
'unnecessary contracts' is the wordplay.
'unnecessary' becomes 'needless' (similar in meaning).
'contracts' means to remove the last letter (I've seen 'contract' mean this (contract can mean to shorten)).
'needless' with its final letter taken off is 'NEEDLES'.
(Other definitions for needles that I've seen before include "Annoys, pointers" , "IoW rocks" , "passes through" , "Pins and - -" , "Where a lighthouse is" .)