Butcher's bill that's used by couples? (5,7)
I believe the answer is:
joint account
'butcher's' is the definition.
Both the definition and answer are singular nouns.
Maybe there's an association between them I don't understand?
'bill that's used by couples?' is the wordplay.
'bill' becomes 'account' (synonyms).
'that's used by' says to put letters next to each other.
'couples?' becomes 'joint' (I can't justify this - if you can you should give a lot more credence to this answer).
'account' after 'joint' is 'JOINT ACCOUNT'.
Can you help me to learn more?
(Another definition for joint account that I've seen is " In which both can save".)