…forth laws against noisy left-wingers (4)
I believe the answer is:
flan
'forth laws' is the definition.
I can't judge whether this defines the answer.
'against noisy left-wingers' is the wordplay.
'against' means one lot of letters go next to another.
'noisy' becomes 'f'.
'left wingers' becomes 'lan' (I am not sure about this - if you are sure you should believe this answer much more).
'f' next to 'lan' is 'FLAN'.
Can you help me to learn more?
(Other definitions for flan that I've seen before include "Quiche-like dish" , "Open-topped pie" , "Open pastry case with savoury filling" , "Open-topped tart" , "it may get jammed" .)