Unused neck dressing suitable for some joints (4,5)
I believe the answer is:
mint sauce
'suitable for some joints' is the definition.
I can't tell whether this definition defines the answer.
'unused neck dressing' is the wordplay.
I cannot quite see how this works, but
'unused' could be 'mint' (I've seen this in another clue) and 'mint' is found in the answer.
'dressing' could be 'sauce' (I've seen this before) and 'sauce' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for mint sauce that I've seen before include "It goes with roast lamb" , "gravy" , "Roast lamb condiment" , "Usual flavouring for lamb or mutton" , "that's over Sunday lunch?" .)