Thus fill a shoe and shut up! (3,1,4,2,2)
I believe the answer is:
put a sock in it
'shut up' is the definition.
I don't know anything about this answer so I cannot tell whether this works.
'thus fill a shoe and' is the wordplay.
I cannot quite see how this works, but
'thus' could be 'so' (synonyms) and 'so' is found in the answer.
'a' is within the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for put a sock in it that I've seen before include "Shut up!; tuition packs (anag.) (3,1,4,2,2)" , "Quiten down" , "pipe down" , "Keep mum" , "Stop endless yacking" .)