Yearning for a noise from the cash register (6)
I believe the answer is:
aching
'yearning' is the definition.
('ache' can be a synonym of 'yearn')
'a noise from the cash register' is the wordplay.
I cannot really see how this works, but
'a' is present in the answer.
'from' could be 'in' (I've seen this in other clues) and 'in' is present in the answer.
'cash' could be 'c' and 'c' is located in the answer.
This may be the basis of clue (or it may be nonsense).
'for' is the link.
Can you help me to learn more?
(Other definitions for aching that I've seen before include "Feeling pain" , "Giving continuous pain" , "Causing discomfort" , "Yearning; in pain" , "Continuously sensitive" .)