Payment made when the gang are at their wits' end (5)
I believe the answer is:
screw
'end' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Maybe you can see a link between them that I don't see?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for screw that I've seen before include "Threaded bolt" , "Fastener with a tapered threaded shank" , "may need a driver" , "[TURNKEY]" , "Apply backspin (snooker)" .)